Click on a thumbnail graphic to view a gallery of drought data from the US Drought Monitor.

US Drought Monitor November 5, 2019.

West Drought Monitor November 5, 2019.

Colorado Drought Monitor November 5, 2019.

Click here to go to the US Drought Monitor website. Here’s an excerpt:

This Week’s Drought Summary

This U.S. Drought Monitor week saw continued improvements in drought conditions as a large-scale, low-pressure system last week delivered moderate-to-heavy precipitation accumulations ranging from 2 to 7 inches leading to widespread improvements across portions of the South, Southeast, Mid-Atlantic, and the lower Midwest. For October, these regions saw well-above-normal precipitation that has helped alleviate drought conditions, especially in the Southeast. Out West, generally dry conditions prevailed with the exception of some mountain snow showers in the central and northern Rockies of Montana, Wyoming, and Colorado. In California, fire-weather conditions improved allowing firefighters in southern and northern California to help contain several large wildfires. According to the NOAA National Centers for Environmental Information (NCEI), the contiguous U.S. experienced its 21st coolest and 8th wettest October on record…

High Plains

On this week’s map, no changes were made across the region. For the week, the entire region was relatively dry with below-normal temperatures. Average temperatures ranged from 2-to-20 degrees below normal with the greatest negative anomalies observed in north-central and eastern Wyoming as well as eastern Colorado. According to NOAA NCEI, the Northern Rockies and Plains Climate Region experienced its 4th coolest and 26th wettest October on record. Additionally, the region had its wettest 3-month (Aug-Oct 2019), 9-month (Feb-Oct 2019), and 12-month (Nov 2018-Oct-2019) periods on record…

West

On this week’s map, no changes were made in the region. An on-going assessment of the abnormally dry conditions in California (since the beginning of the wet season) is currently underway by the U.S. Drought Monitor and the California Drought Coordination Team in order to ascertain the spatial extent and possible impacts being observed across the state. From a hydrologic perspective, despite below-normal precipitation during the past 60 days, nearly all of California’s major reservoirs are currently at or above historical averages for this time of year. Elsewhere in the region, portions of the central and northern Rockies received some snow shower activity during this past week. According the NWS NOHRSC’s regional snow analyses, 68.8% of the Northern Rockies and 59.7% of the Central Rockies are currently covered by snow. Additionally, the NRCS SNOTEL network is showing above-normal Water Year to Date (Since Oct 1) precipitation (liquid and frozen) in the mountains of northeastern Oregon, central Idaho, western Montana, northern Wyoming, and north-central Colorado. Elsewhere, stations are reporting below-normal precipitation for the same period. According to NOAA NCEI, the West Climate Region experienced its 11th driest and 19th coolest October on record while the Northwest Climate Region had its 49th driest and 2nd coolest October…

South

One this week’s map, recent rainfall across eastern portions of Texas, Arkansas, Louisiana, Mississippi, and Tennessee led to continued widespread improvement in conditions. Rainfall accumulations across the region ranged from 1 to 8 inches with the heaviest accumulations observed in Mississippi. This week’s precipitation improved soil moisture and streamflows leading to one-category improvements in areas of Severe Drought (D2), Moderate Drought (D1), and Abnormally Dry (D0). In portions of southern, central, and western Texas, dry conditions prevailed leading to some minor expansion of drought. As a region, the South experienced its 23rd wettest October on record, while at a state level Mississippi experienced its wettest October on record. For the week, average temperatures were below normal across the entire region with the greatest negative anomalies observed across the northern half of Texas and western Oklahoma where temperatures were 10-to-20 degrees below normal. As a region, the South Climate Region had its 36th coolest on record for October…

Looking Ahead

The NWS WPC 7-Day Quantitative Precipitation Forecast (QPF) calls for moderate-to-heavy accumulations ranging from 1 to 4 inches across a swath extending from northern Texas to Kentucky later this week. Further south, light-to-moderate accumulations (1-to-2 inches) are expected along the Gulf Coast and in south Texas. Along the Great Lakes and the Northeast, periods of precipitation (accumulations generally <1 inch liquid), including some heavy lake-effect snowfall, are expected. Out West, primarily warm and dry conditions will prevail with the exception of northern portions of the Pacific Northwest and northern Rockies that may see periods of mountain snow. The CPC 6–10-day Outlook calls for a high probability of above-normal temperatures west of the Rockies while areas east of the Rockies are expected to be below normal. In terms of precipitation, there is a moderate-to-high probability of below-normal levels across most of the West including the Intermountain West, Great Basin, California, and the Pacific Northwest while there is a moderate probability of above-normal precipitation in eastern Montana and western portions of the northern Plains. Likewise, above-normal precipitation (moderate probability) is expected in the southern tier from Texas to Florida and extending up the Eastern Seaboard.

Click here to read the current assessment. Click here to go to the NIDIS website hosted by the Colorado Climate Center. Here’s the summary:

It was a colder than normal year for trick-or-treaters across most all of the Intermountain West, as an early cold season arctic airmass dug into the region. Weekly temperature anomalies were more than 15 degrees below normal for much of Utah, Wyoming, and Colorado. October temperatures were a sharp contrast from the much warmer than average September. Utah, Wyoming, and Colorado October temperatures were among the top ten coldest on record going back to 1895.

Last week’s deep cold frontal passage did lead to some decent moisture totals east of the Continental Divide, and some more modest moisture west of the Continental Divide. Headwaters of the South Platte and Arkansas Basins recorded 0.50-1.00″ of precipitation. Most of this moisture fell as snow. Snowpack levels for major river basins across Wyoming, northern Utah, and most of Colorado are above normal to start the season. However, southern Utah and southwest Colorado are still behind on snow. Furthermore, it’s still early. Two weeks of dry weather would erase existing snowpack surpluses.

The Intermountain West continues to balance the impacts of short-term dryness against the impacts of a great 2019 snow season. Surface water supplies in stream and reservoirs are still, by and large, healthy. 7-day average streamflows are beginning to lean dry in the Four Corners area. Meanwhile, southest Colorado is reporting precipitation defictis of 5-10″ since the beginning of July. It will likely take more than a couple storms to close these deficits. Impacts from short-term drought include dry soils, stressed vegetation, difficult winter wheat planting conditions, and stunted late season grass growth for ranchers.

Recent cold weather and snow in the high country has at least mitigated fire concerns. The Decker Fire south of Salida, CO is now 100% contained. As the temperatures cool and the snow settles, we say “farewell” to the 2019 growing season (and hopefully fire season as well). We now play the waiting game to see how WY 2020 snowpack will build across the UCRB. The southern portion of the UCRB will be disadvantaged come springtime by the dry soils in place now. The Variable Infiltration Capacity model is indicating bottom 10th percentile soil moisture storage for southern Utah and western Colorado.

The near-term weather outlook shows dry conditions prevailing across most of the Intermountain West. A large high pressure ridge off the West Coast is blocking Western US access to some much needed Pacific moisture. Models are suggesting 0.25-0.50″ of moisture is likely for southern New Mexico this week, and that another cold front or two may clip eastern Wyoming and northern Colorado. Relief is not currently in sight for the drought-stricken Four Corners area.

From NOAA:

Extremes in both temperature and precipitation characterize October across the contiguous U.S.

For October, the average contiguous U.S. temperature was 52.3°F, 1.8°F below the 20th century average. This ranked in the lowest third of the 125-year period of record and was the coolest October since 2009. Below-average temperatures were observed from the High Plains to the Pacific Coast, while above-average temperatures blanketed the eastern third of the contiguous U.S. Parts of southern Florida were record warm. For the year-to-date, the contiguous U.S. average temperature was 55.5°F, 0.5°F above average, and ranked in the warmest third of the historical record.

The October precipitation total for the contiguous U.S. was 3.14 inches, 0.98 inch above average, and ranked as the eighth wettest October in the historical record. Above-average precipitation fell across much of the eastern half of the contiguous U.S., with record precipitation occurring across portions of the Great Lakes and the Mississippi Valley. Below-average precipitation fell across parts of the West, as well as the central and southern Plains. For the year-to-date, the contiguous U.S. precipitation total was 30.25 inches, 4.89 inches above average, and was the wettest January–October on record. Average precipitation across the contiguous U.S. for the 12-month period November 2018–October 2019 was 36.21 inches, 6.28 inches above average, exceeding the previous November–October record set in 1972–73 by nearly 1.5 inches.

This monthly summary from NOAA National Centers for Environmental Information is part of the suite of climate services NOAA provides to government, business, academia, and the public to support informed decision-making.

October Temperature

Above- to much-above-average temperatures dominated across the East Coast, southern Great Lakes, Ohio Valley, and southern Plains. Florida ranked second warmest during October, while Georgia and South Carolina ranked third warmest.

Record heat blanketed the Southeast and mid-Atlantic states the first week of October, shattering many all-time October heat records.

Below- to much-below-average October temperatures were observed across the Northwest, Intermountain West, Great Plains, and western Great Lakes. Idaho ranked coldest for the month, breaking the 1919 record by 0.8°F. The states of Washington, Utah, and Wyoming ranked second coldest during October.

Great Falls, MT, reported a low of 9°F on October 1 — the coldest temperature on record in Great Falls so early in the fall season.

An early-season snowstorm across the Rockies and Midwest was accompanied by bitter cold temperatures during the last week of October. All-time record low temperature records for October were set across the West with some temperatures dipping well below zero. Peter Sinks, UT, often one of the nation’s coldest locations, dropped to −46°F early on October 30, according to the Utah Climate Center. This temperature may be the coldest October temperature on record across the contiguous U.S.

Alaska ranked in the warmest third of the October record with a statewide average temperature of 30.8°F, 5.3°F above the long-term average. Parts of the North Slope experienced temperatures averaging at least 9°F warmer than the historical average, while much of the Panhandle experienced a mild October. It was the second warmest October for Utqiaġvik (Barrow).

October Precipitation

Above- to much-above-average precipitation was observed across much of the eastern half of the contiguous U.S. Mississippi ranked wettest during October, while 11 additional states ranked among their 10 wettest Octobers on record.

Below- to much-below-average precipitation occurred across the West, with Arizona and California ranking among their 10 driest Octobers on record.

An upper-level trough and an associated cold front brought the northern Rockies and Plains their first significant snowstorm of the season. From October 9–13, one to two feet of snow accumulated across portions of Montana and North Dakota, with several locations noting their snowiest start to the season. Great Falls, MT, reported 27 inches of snow while Bismark, ND, measured 17.1 inches for the season-to-date.

Another early-season snow storm impacted the central Rockies and parts of the Plains and Midwest. Denver reported 6.6 inches of snow on October 29 — the largest one-day October snowfall for Denver since 2011. Snow from this system also fell across portions of the central Plains and Great Lakes.

October was wet across much of Alaska with portions of the Northeast Interior, Southeast Interior, and West Coast divisions reporting record wet conditions for the month.

According to the October 29 U.S. Drought Monitor report, approximately 18 percent of the contiguous U.S. was in drought, down slightly from 19 percent at the beginning of October. Drought conditions became less severe across parts of the Southeast, Tennessee and Ohio valleys, Texas, the Alaska Panhandle, Hawaii, and Puerto Rico. Drought intensified across the Four Corners region of the Southwest.

Extremes

Subtropical Storm Melissa formed from a slow-moving East Coast nor’easter on October 11 with sustained winds of 65 mph. Impacts from Melissa included coastal flooding from Virginia to New York. Less than a week later, a mid-latitude cyclone, moving across the central and eastern United States, developed into a “Bomb Cyclone” (a storm whose central pressure drops by at least 24 millibars in 24 hours or less). This storm packed wind gusts up to 90 mph in southern New England on October 17 and left over 500,000 residents without power. New October low-pressure records were reported for various locations across Massachusetts, Rhode Island, and New Hampshire. Precipitation accumulations from this storm system measured between two and four inches across portions of New England.

Post-Tropical Cyclone Nestor made landfall on October 19 near Apalachicola, FL, with top sustained winds of 45 mph. The system brought between three and five inches of rainfall as well as tornadoes to the Florida Panhandle. Beneficial rains from the remnants of Nestor fell across parts of Georgia, South Carolina, North Carolina, and Virginia, which had been impacted by severe drought conditions.

Tropical Storm Olga merged with a cold front in the Gulf of Mexico on October 25 and made landfall as a post-tropical storm along the central Louisiana coast early the next morning. Many residents lost power across Louisiana as winds exceeded 70 mph, while tornadoes and wind damage impacted both Mississippi and Alabama.

Several large and dangerous wildfires impacted parts of north-central and southern California during October and remained active at the beginning of November. The Kincade Fire, located in north-central California, burned through nearly 78,000 acres and destroyed almost 350 structures by the end of October. The Tick, Saddleridge, and Getty fires in southern California consumed more than 14,000 acres as well as 60 structures. The Easy Fire, also located in southern California, consumed more than 1,700 acres by the end of October. These large and dangerous fires were fanned by powerful winds, with some gusts topping 100 mph in the Sierra Nevada range. Across southern California, unusually strong Santa Ana winds made it difficult for fire crews to keep these fires from spreading.

Year-to-date (January–October) Temperature

Above- to much-above-average year-to-date temperatures were observed from California to the southern Plains and from the Southeast to New England. Record warm temperatures were scattered throughout much of the Southeast and mid-Atlantic states. Thirteen states had a top 10 warm year-to-date period with Florida, Georgia, South Carolina, North Carolina, Virginia, and West Virginia reporting their warmest January–October on record.

Below-average temperatures occurred across the northern Plains and parts of the Midwest with South Dakota having its seventh coldest year-to-date period on record.

Alaska had its second warmest January–October on record. Record heat blanketed much of the North Slope and northern West Coast with portions of the Aleutians, the Northeast Interior, and Central interior also reporting record warm conditions. The rest of the state had above- to much-above-average temperatures for this 10-month period.

Year-to-date (January–October) Precipitation

Above-average January–October precipitation dominated much of the country with record wet statewide ranks occurring in South Dakota, Minnesota, Wisconsin, Illinois, and Michigan. Below-average precipitation fell across the Pacific Northwest, parts of the Southwest and Southeast.

Globally, October was 0.69°C warmer than the average October from 1981-2010, making it by a narrow margin the warmest October in this data record. Europe generally saw above-average temperatures, with the exception of most of the north and north-west of the continent. Temperatures were much above average in large parts of the Arctic, while much of western USA and Canada experienced much below average temperatures.

October temperatures in 2019 were above the 1981-2010 average for most of Europe, especially so in the east and south-east. Below-average temperatures occurred over most of the north and north-west of the continent.

Elsewhere, temperatures over the northern hemispheric land masses were markedly above average over parts of the Arctic, over the eastern USA and Canada, and over the Middle East and much of North Africa and Russia. Temperatures were likewise well above average over southern Brazil, southern Africa, western and southern Australia, and most of eastern Antarctica.

Temperatures over land were substantially below average over a region encompassing much of the western USA and Canada. They were also below average in parts of tropical Africa and Antarctica, and to a lesser degree over several other regions.

Regions of below-average temperature occurred over all major oceans, including the tropical eastern Pacific and the ice-covered Weddell Sea. Air temperatures over sea were nevertheless predominantly higher than average, especially so over several Arctic and Antarctic seas and over the north-eastern Pacific Ocean.

Global temperatures were substantially above average in October 2019. The month was:

0.69°C warmer than the average October from 1981-2010, making it by a narrow margin the warmest October in this data record;

an insignificant 0.01°C warmer than October 2015, the second warmest October;

0.09°C warmer than October 2017, the third warmest October.

From NOAA (Michelle L’Heureux):

The Pacific Ocean is throwing a bit of a temper tantrum these days, but it’s not where you think it might be. Often we focus on the tropical Pacific Ocean because it’s where ENSO takes center stage, but currently temperature departures across the Tropics are pretty blah. Instead, for the past few months, it’s the North Pacific Ocean that pops out at you—a gigantic red sore that covers much of the eastern basin.

As our colleagues over at NOAA Fisheries explained last month, this feature is a Marine Heatwave. Marine heatwaves are considered prolonged, large-scale warm water events (1). Back in 2014-16, people started calling a very prominent North Pacific marine heatwave THE BLOB. Now, some people are saying this current event could be a return of the Blob. Blob is fun to say and simply rolls off the tongue, so we understand why it’s caught on.

BUT! The problem is “Blob” is not that useful of a description. There’s no single fixed Blob. As Michael Jacox points out, it would be like if we called every single hurricane, “Hurricane Dave.” Obviously hurricanes, like marine heatwaves, don’t always occur in the same place, at the same time, have the same magnitude, or even have the same areal coverage. In fact, an El Niño can result in conditions that would be considered a marine heatwave in the Tropics, but we would not call that area of warmth a “Blob.”

Marine heatwaves can be a bit tricky to categorize because, like most phenomena in weather and climate, there are shades of grey. While marine heatwaves can be defined by many different physical properties (e.g. size, intensity, duration), there are no fixed set of impacts that will always result. At this point, it is too early to say if this heatwave might have major impacts on marine life and fisheries the way the last one did (2).

To learn more, I convened an expert panel to ask some questions. The interviewees are Michael Alexander at NOAA Earth Systems Research Lab and Michael Jacox and Nate Mantua, who are with NOAA Southwest Fisheries Science Center. They had a lot of great information to share —so much in fact that we’re well over our length limits (for those who want the “extended interview” keep scrolling!).

Q: So far, how different is the current marine heatwave (Blob Redux) from the one we saw in 2014-16 (The Original Blob)?
Alexander: Marine heatwaves are usually identified by temperatures at the sea surface, which can be measured by satellites. Based on sea surface temperatures, the general pattern of the current heatwave does resemble the Original Blob. However, generally, it is important to determine how deep the temperature anomalies (how much warmer or colder the temperature is relative to average) extend into the ocean. As Nate points out below, these anomalies are just near the surface off the US West Coast, so strong storms, which often begin this time of year, can quickly wipe out a heatwave. In fact, we may have just started seeing this.

Mantua: The biggest differences so far are in the depth and duration of the two events. The Original Blob lasted for multiple years and the warming eventually extended to more than 300 meters (~1,000 feet) below the surface across much of the Northeast Pacific. In contrast, the current event has been with us for only a few months, and the extreme warming is confined to the top 30 to 50 meters (~100-150 feet).

Q: Around the time the marine heatwave emerged in the North Pacific Ocean in 2014, there was an El Niño Watch. How significant is ENSO in helping fuel marine heatwaves (or vice versa)?
Alexander: The 2014 marine heatwave (Original Blob) started in the northeast Pacific. Recent studies suggest that air-sea interactions allow ocean temperature anomalies near Hawaii to move towards the equator. When warm temperature anomalies, including marine heatwaves, reach the equator they enhance the chance of an El Niño event in the following year (Dan Vimont talked about this in an earlier blog post). So the Blob may have contributed to the strong El Niño event that occurred in 2015-16.

While El Niño events occur in the tropical Pacific they influence the ocean and atmosphere in the North Pacific including sea surface temperatures. Generally, the winds are from the southwest near the US West Coast during El Niño which warms the underlying ocean, while ocean processes push the deeper cold water farther down, warming a very narrow region right near the coast. A full blown El Niño did not happen in 2014 but one did in the following winter, which likely contributed to the continuation of the marine heatwave when it was strongest near the West Coast.

Jacox: In general, El Niño is a very prevalent cause of marine heatwaves in much of the Pacific. Off the U.S. West Coast, El Niño events tend to produce warming by changing the wind patterns that typically cool the coastal ocean, and through an “oceanic teleconnection” where coastal trapped waves propagate northward along the North American west coast. The Original Blob wasn’t caused by El Niño, but the tropical warmth during the 2014-15 winter likely helped that heatwave persist and then the strong 2015-16 El Niño contributed to the extended warming as well.

Mantua: Georgia Tech Professor Emanuel Di Lorenzo and I published a study showing that the evolution and persistence of the Original Blob involved long-distance teleconnections between the North Pacific and Tropical Pacific that involved two flavors of El Niño. As Mike J. points out, the initial warming off the coast of the Pacific Northwest that first earned the “Blob” label wasn’t caused by El Niño. Instead, the atmospheric forcing that started The Blob in winter 2013/14 also contributed to the tropical warming in 2014, which persisted into 2015.

Q: There are research studies that indicate that that marine heatwaves will become more frequent with climate change. How certain is this? Could there be a human-caused thumbprint in recent events?
Alexander: Most of the ocean has warmed over the past 50 years. This warming is projected to continue through the 21stcentury, especially off the northeast US coast. Nearly all computer model simulations of the future indicate the oceans will warm. So relative to the present, marine heatwaves will become more frequent. However, if one thinks of a heatwave as a short-term event relative to the mean temperature at that time, the frequency of marine heat could stay about the same but just happen in an overall warmer climate.

Jacox: What those studies show is that in a warming ocean, historical temperature thresholds will be exceeded more often. In other words, temperatures we currently consider extreme will become more common. But that doesn’t mean marine heatwaves will necessarily change. One could think of it like sea level rise – just because the water gets higher doesn’t mean the waves are getting bigger. How marine heatwaves will change relative to the increasingly warmer temperatures is still an open question, and the answer will likely be different in different parts of the ocean. For marine species, both the warmer temperature and future marine heatwaves will be important. Their relative and combined impacts will vary among species depending on their exposure to warmer temperatures, their sensitivities, and their adaptive capacity.

Q: Perhaps the most important question of all: If you got the Blob, Polar Vortex, and Godzilla El Niño into the ring, which one would win?
Alexander: My dog, which can eat just about anything and drink vast quantities of warm water.

Jacox: Trick question, it turned out that the Blob and Godzilla El Niño were on the same team.

Mantua: I’m with Mike and Mike on this one.

Q: Right now we’re ENSO-neutral, so it doesn’t seem like ENSO would be a contributor to the current heatwave. I know the heatwave is ongoing and in-depth study of it will have to wait, but, at this point, can you point at some leading suspects?
Alexander: The Blob formed under a strong stationary “blocking” atmospheric high-pressure system. The associated weak winds and warm air temperatures allowed the near-surface ocean to heat rapidly. Surprisingly, blocking events over the North Pacific are actually more common during La Niña (the cold phase of ENSO) then during El Niño. Other processes can influence weather patterns over the North Pacific including the Madden-Julian Oscillation. Changes in ocean currents, such as the Gulf Stream in the Atlantic and Kuroshio current in the Pacific may influence marine heatwaves over longer periods of time.

It is important to always keep in mind that weather patterns, like blocking, can occur randomly due to the chaotic nature of the atmosphere. Thus, while ENSO might influence the types of weather patterns it does not control them outright– think of asking your 2-year-old son or 12-year-old daughter to do something, they might listen to you, what maybe 60% of the time (if you’re lucky).

Mantua: My short list of suspects includes (1) teleconnections from the tropical Indo-Pacific region, which this summer had persistently high ocean temperatures around the International Dateline, cool temperatures in the eastern Indian Ocean, and persistent tropical rainfall anomalies in southeast Asia/Indonesia; (2) the extraordinarily warm Arctic, and (3) bad luck – due to the random nature of our climate. This year’s marine heatwave formed under a strong stationary “blocking” atmospheric high over Alaska in spring and summer, and a persistent area of lower-than-normal sea level pressure between Hawaii and the mainland for most of summer. These pressure patterns weakened the normal wind systems over the North Pacific and Bering Sea that are important for the upper ocean’s heat balance. Another interesting feature of summer 2019’s climate has been a circumpolar teleconnection in the jet stream that included persistent high pressure ridges over Alaska, Greenland and the Russian Arctic. And finally, there may be positive feedbacks between the warming of the North Pacific and the weak wind patterns that caused the warming in the first place. Part of the bad luck behind this event may be the combination of some or all of these different factors.

Q: Can some of the factors we’ve discussed above help us predict marine heatwaves? How far out do you think they can be predicted?
Alexander: The Blob was not well forecasted. We might only be able to predict the actual pattern and strength of marine heatwaves a few weeks out, but given the large-scale factors that influence them we may be able to predict the probability of an event occurring, like the percent chance of rain you see when you check the weather on your cell phone.

Jacox: It really depends on what’s driving the heatwave. The initial formation of the Blob wasn’t predicted even a month or two in advance, and neither was the ongoing heatwave in the northeast Pacific. But a marine heatwave that results from a strong El Niño event has much greater potential to be predicted, even 6 months or more in advance. There may also be predictability for the evolution of heatwaves like the Blob after they form, even if they weren’t predicted initially.

Q: Back in 2014-15, there was some concern that the Blob was causing an atmospheric ridge over the eastern North Pacific Ocean and this was leading to more drought on the West Coast. Now that the data is in, how likely was it that Blob was causing the ridge? Can you discuss the interplay between these marine heatwaves and the large-scale circulation above them?
Mantua: My read of the latest research is that it is not likely that the Blob caused the ridge. Several studies (this blog post) point to some atmospheric changes caused by the combined influence of the warm SST anomalies in the western tropical Pacific and cold SST anomalies in the eastern tropical Pacific. However, there is also some published modeling work showing a modest wintertime mid-latitude ridge response to the Blob in winter 2013-14. It may be that warming in the Northeast Pacific Ocean does not cause, but may help persist the ridge pattern (and persistence of the warming), at least in winter.

For low-elevation areas exposed to the atmosphere’s marine boundary layer on the West Coast this summer, there appears to be a direct connection between elevated SSTs and higher dew point temperatures and higher nighttime low temperatures. Cliff Mass at the University of Washington has a nice blog post that includes high-resolution modeling results showing this. Additionally, Nick Bond has shown that February SSTs in the Original Blob region are positively correlated with spring time air temperature in Washington.

Click on a thumbnail graphic to view a gallery of snowpack data from the NRCS.

Snowpack Colorado November 4, 2019 via the NRCS.

Upper Colorado River Basin High/Low snowpack graph November 4, 2019 via the NRCS.

Gunnison River Basin High/Low snowpack graph November 4, 2019 via the NRCS.

Laramie and North Platte Basin High/Low snowpack graph November 4, 2019 via the NRCS.

Upper Rio Grande River Basin High/Low snowpack graph November 4, 2019 via the NRCS.

San Miguel, Dolores, Animas, and San Juan Basin High/Low snowpack graph November 4, 2019 via the NRCS.

South Platte River Basin High/Low snowpack graph November 4, 2019 via the NRCS.

Yampa and White Basin High/Low snowpack graph November 4, 2019 via the NRCS.

Statewide Basin High/Low snowpack graph November 4, 2019 via the NRCS.

Arkansas River Basin High/Low snowpack graph November 4, 2019 via the NRCS.

From The Denver Post (Chris Bianchi):

The highest snowpack levels are in northern Colorado, where some areas are more than three times above where they should be for early November. Most of the snowfall came over the past two weeks, as a series of strong and exceptionally cold storm systems moved through the state, dumping feet of snow across the northern mountains. Because most of October’s snow events arrived from the north, Colorado’s northern mountains — the Park, Medicine Bow and Front Ranges — saw the most overall snowfall.

Because of that, though, some parts of southern Colorado are running a tick behind average snowpack levels, as of Friday’s update.

Of course, all of that snow also has ski resorts reporting record snow levels and opening earlier than usual. It’s also has forced the earliest closure of Independence Pass in nearly a decade.

That said, October statewide precipitation — a measure of the overall moisture — was only 82% of average, based on NRCS data. Because colder air can hold less water than warm air, there is typically a correlation between a colder-than-average month and lower precipitation amounts.

That means the majority of the state officially remains in a drought, according to the United States Drought Monitor’s most recent update. More than 80% of the state is considered to be abnormally dry.

After all of the recent snow, though, no significant snowfall appears to be in the near-term forecast. A generally dry pattern will limit snow chances for most of the state over the next week to 10 days.

From The Denver Post (Chris Bianchi):

Denver finished with an official total of 12.5 inches of snowfall last month, making it the city’s snowiest October at Denver International Airport since 2009. However, at the city’s more centrally-located Stapleton Airport observation site, Denver finished with 15.7 inches of snowfall, making it the snowiest October there since 1997. It was also Stapleton’s second-snowiest October in the last 50 years.

Temperature-wise, Denver finished with an average reading of 43.7 degrees over the full month of October, Denver’s fourth-coldest October on record. It was Denver’s coldest October overall since 2009…

Colorado Springs tied its third-coldest October on record, and Pueblo saw its second-coldest. Those were just one of dozens of record cold temperature readings statewide in October.