wxgeek's weather-Severe Storms Possible Mon-Tue-Update 6/20

Update Thu Jun 20

Weak cold front moved through northeast CO last night, which has brought in easterly winds along the plains into the lower foothills with slightly higher RH values. This regime will transition to a warmer, drier and windier regime later this afternoon. South to southwest winds will develop this afternoon, but remain lighter than Wed with speeds of 10-20 mph. Winds should die down after sunset. Temps will remain well above seasonal norms in the extended period. Southwest flow will increase on Friday with wind speeds of 15-35 mph possible and very low RH values (under 15%), so red flag conditions to persist across most of the state once again.

Really not much change in the current pattern through the end of next week. Hot temps, low RH values and occasionally windy conditions is the outlook. Winds will generally be from the south to west, so fire movement generally towards the north with spreading to the northwest and northeast likely through the middle of next week. Late next week flow aloft becomes more westerly to northwesterly as upper ridge builds over the Rocky Mountains, which will create even warmer temps. No precip is currently forecast by any models through next Friday, with some precip possible by next weekend as some moisture becomes trapped under large high pressure some aloft. However, no real significant precip is likely.

_________________
"Climatology is what you expect, Weather is what you get".

"It is better to be roughly right than precisely wrong".

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Update Tue Jun 18

Storms beginning to fire off along the mountains and foothills and will continue to spread east onto the Urban Corridor and Plains. Severe threat exists again today mostly east of I-25 corridor with large hail and damaging winds possible, along with an isolated tornado or two. Mostly just small hail and gusty outflow winds along with lightning west of I-25. Storm motion again today from the west to west-northwest at 10-20 mph. Should be our last chance for precip for a while, so savor every drop.

Beginning Wednesday, we are in for an extended period of hot, breezy and dry weather. Latest models bring south to westerly winds of 15-30 mph into the foothills and adjacent plains Wed-Fri, so expect RH values to drop below 15% many areas and red flag conditions to exist over much of the state, especially Wed and Fri. Temps will be in the low to mid 90's on the plains, so mid 70's to 80's in the foothills. Weak cold front brings slightly cooler air in on Sunday, but then upper ridge builds back in with a vengeance next week, so we could see near record temps much of next week, with more wind, low RH values and no precip in the forecast. All in all, a very bad next 7-10 days with respect to fire danger.

Looking way ahead, we can now only hope for an early onset to the North American Monsoon. Long range models indicate some hope the first week of July as a tropical system is forecast to move into the western Gulf of Mexico, which could jump start the Monsoon the first week of July.

_________________
"Climatology is what you expect, Weather is what you get".

"It is better to be roughly right than precisely wrong".

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General to possible severe thunderstorms will be possible today and Tuesday across much of eastern CO from the foothills east. General storm motion will be from the west northwest today and Tuesday as storms form in the mountains and foothills and move out onto the plains. Biggest concern will be damaging hail and winds, although some tornadoes will be possible. Storms will dissipate overnight, but will fire up again Tuesday afternoon and evening. Frequent lightning will accompany storms, so fire starts are possible, although precip will also accompany most of these storms which will limit fire starts. Temps to remain near normal today and Tuesday.

From Wednesday into this weekend and likely into most of next week, warm, breezy and dry weather will persist over most of CO. Upper ridge shifts slightly east with upper trough along the West Coast, so CO will remain under dry southwest flow aloft. This scenario will lead to temps 5-15 degrees above normal, low RH values and gusty south to southwest winds which will create dangerous fire weather conditions for the extended outlook. Models suggest these conditions will persist into late next week, with the potential for precip moving back into CO by next weekend. Any new fire starts will have the potential for explosive growth. Hopefully recent fire bans and common sense will limit potential ignition sources. Also, this period will hopefully be the last severe fire weather period before the Monsoon kicks in, which will greatly reduce fire danger. Then the second phase of fire season starts in September and the intensity is determined by how wet the Monsoon season was, specifically August into September.

_________________
"Climatology is what you expect, Weather is what you get".

"It is better to be roughly right than precisely wrong".

Bump for Tuesday 6/18 update

Bump for Thursday 6/20 update