Western U.S. faces threat of out of control fires Friday

WEATHER NEWS: Western U.S. faces threat of out of control fires Friday


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Out-of-control fires were erupting in New Mexico and Colorado late Friday due to combination of ferocious winds, extremely low humidity, high temperatures and drought. Forecasters had described the situation as “dire” ahead of the flare-up.

On Friday afternoon into the evening, numerous fires had erupted in New Mexico and Colorado amid winds gusting over 60-70 mph (additional blazes were also reported in Kansas and Nebraska):

The strong winds were also blowing up large amounts of dust, prompting dust storm warnings and degrading air quality.

“At 2 pm the Air Quality Index in #Albuquerque is so bad that it is “Beyond” the ‘Index,’” tweeted Joe Diaz, chief meteorologist for the ABC affiliate in Albuquerque. “Basically everyone should stay indoors and reduce activity levels until conditions improve.”

Wildfire smoke and dust also filled the skies over Denver Friday evening, after it set a record high of 89 degrees.

Denver, Colorado Springs and Albuquerque were among areas that the National Weather Service placed in its “extreme” risk zone for fire danger Friday, affecting 4.2 million people. Boulder, Colo., and El Paso were in a slightly less severe “critical” risk zone.

The Albuquerque office warned early Friday that there was “high confidence that a widespread extreme and potentially catastrophic fire weather event will occur.”

In its forecast discussion, the office wrote: “a dire weather situation expected today as very to strong to damaging winds develop along with exceptionally low humidity that will create extreme fire weather conditions.”

It described the potential for “incredibly strong” winds, with widespread gusts to 60 to 70 mph and even a few instances of 80-mph gusts.

“When it comes to wind and fire weather, there are bad days, really bad days, and really, really bad days,” the office tweeted. “Friday is going to be a really, really bad day.”

The Weather Service office in Boulder, serving eastern Colorado, sounded a similar alarm.

“The strong wind speeds expected would be disastrous for any fires that may start making wildfire control impossible,” it wrote.

Both offices urged residents to avoid outdoor burning or any other activity that might ignite a spark; otherwise the results could be “catastrophic,” the Albuquerque office said.

The Boulder office conveyed a stark warning to residents: “If you live in a vulnerable area, it would be prudent to have a go bag ready with important documents, medications, and valuables in the event of an evacuation.”

The same powerful storm system generating the dangerous winds over Colorado and New Mexico was predicted to ignite severe thunderstorms on its warm side from the Texas Panhandle to South Dakota. In the cold air on its northwestern flank, blizzard warnings were in effect in the western Dakotas and northern Rockies for the second time in 10 days, with more than a foot of snow and 50 mph wind gusts set to deliver whiteout conditions.

The storm was being fueled by remarkable temperature contrasts. The mercury soared toward record-breaking highs in the upper 80s in eastern Colorado and 90s in the Central Plains on Friday afternoon, but they were forecast to plummet into the 20s in the northern Rockies and northern Plains at night as rain turns to wind-swept snow.

Red-flag warnings for high fire danger cover southern Arizona to central Nebraska.

The fire threat is being fueled by an insurgence of arid air from the Desert Southwest and powerful winds that will transform an already dry landscape into a tinder box. Relative humidity percentages are predicted to tank into the single digits in many areas.

Even before this insurgence of dry air, extreme to exceptional drought covered much of the landscape. Some areas have received only about a quarter of their typical rainfall over the past 90 days.

Denver is off to its driest start to April since 1963 and has seen no measurable snow this month.

High temperatures, near records, will exacerbate the situation by speeding up the drying of the air and ground. In Denver, highs are forecast to reach the mid-to-upper 80s, its warmest day of the year so far.

The winds are being driven by a low pressure ejecting out of the Intermountain West and slipping north of the Sand Hills of Nebraska, dragging a dryline east over the High Plains. That’s the leading edge of bone-dry air descending down the mountains. That induces “downsloping,” or the heating up and drying out of a pocket of air.

That downsloping air will accelerate to the east in the wake of low pressure, spilling over the mountains and contributing to strong winds gusting to at least 40 to 60 mph. High-wind warnings blanket much of central Nebraska and Kansas, the Oklahoma Panhandle, eastern Colorado and most of New Mexico.

In some parts of eastern Colorado and the western Plains, there is a risk of lightning as thunderstorms erupt near the dryline, which could serve as an ignition source for blazes.

Here’s what to know about dry thunderstorms and how they increase wildfire risk

The winds will spike after just after dark in many locales behind a cold front that will eventually catch up to the dryline.

The Desert Southwest is already dealing with a spattering of wildfires. As of Thursday, 10 uncontained fires were burning in New Mexico, Arizona and Texas; among them, the 20,198-acre Tunnel Fire northeast of Flagstaff that has prompted evacuations and forced the closure of U.S. Highway 89.

Dangerous fire weather conditions will persist into Saturday to the southeast of Friday’s bull’s eye, with a “critical risk” area drawn in eastern New Mexico and the Texas and Oklahoma panhandles. Lubbock, Amarillo and Santa Fe are in that zone.

Tunnel Fire in Arizona nearly triples in size amid high winds

The 2022 wildfire season is off to an above-average start, with most activity concentrated in the Southwest, Plains and Southeast. So far, more than 832,000 acres have burned, compared with an average of about 640,000 acres, according to the National Interagency Fire Center.

Scientists have determined human-induced climate change is intensifying the fire risk by increasing temperatures, which dries out the land surface more quickly and makes it more combustible.

On the northern side of the low-pressure zone, moisture wrapping northwest around chilly air dragged down from Canada will fall as heavy snow which, combined with strong winds topping 50 mph, will lend itself to producing blizzard conditions. Northeastern Wyoming, extreme northwestern South Dakota, eastern Montana and western North Dakota are under a blizzard warning.

Precipitation will spread over the northern Plains and parts of the northern Rockies on Friday evening, beginning initially as rain or mix before subfreezing air becomes more deeply entrenched as low pressure intensifies. Saturday will be dominated by an arc of moderate to heavy snow in the western Dakotas that will hover for 12 or more hours in any given area before slowly progressing east into Sunday.

Winds gusting 35 to 50 mph, and perhaps up to 60 to 75 mph in northwest South Dakota, will loft freshly fallen snow and whip about anything that’s coming down, leading to reduced visibilities. So long as visibilities dip below a quarter-mile for three consecutive hours as winds frequently gust over 35 mph, the criteria for a blizzard will be met.

The combination of heavy, wet snow and strong winds will probably cause tree damage and lead to power outages.

Northern Plains, northern Rockies face second blizzard in 10 days

It’s the second blizzard in 10 days for the north central Lower 48; parts of western North Dakota saw up to three feet of snow last week. A widespread 8 to 14 inches of snow appears likely this time around, with pockets of a foot and a half or more possible.

Severe thunderstorm chances

On Friday, the Weather Service’s Storm Prediction Center drew a level 3 out of 5 “enhanced risk” of severe thunderstorms over central Nebraska, western Kansas and the Oklahoma and Texas Panhandles. Amarillo, Tex.; Kearney and North Platte, Neb.; and Garden City and Dodge City, Kan., are in that zone.

Severe thunderstorms will erupt along the dryline on Friday afternoon and evening from the Texas Panhandle to western Kansas and southwest Nebraska.

“Very large hail and damaging straight-line winds, in addition to at least a few tornadoes are anticipated,” the Storm Prediction Center wrote.

A level 2 out of 5 slight risk is up on Saturday from the Oklahoma Red River to northern Minnesota, including Oklahoma City, Tulsa, Kansas City, Des Moines, Omaha and Minneapolis. Sunday features a level 1 out of 5 marginal risk in a strip from Texas to Michigan.

Damaging winds and hail are the main threat both weekend days. However, a few quick-hitting tornadoes can’t be ruled out as storms propagate to the east and redevelop. The storms will be outrunning the energetic jet stream dip that once contributed to their genesis, however, meaning severe weather risk will wane each day.





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