wxgeek's weather-Above Avg Precip Expected Thru The End of May-Update 5/16

Upper trough currently positioned in UT and will move across CO during the day today. Showers already developing along and west of the Divide, and these will increase in coverage and intensity as they move east across eastern CO this afternoon and evening. Atmosphere is moist and slightly unstable today, so expected thundrestorms to develop, and some to possibly become severe mostly east of I-25 with large hail and tornadoes possible. Snow level will lower to 8500-9500 ft late this afternoon and evening, but I do not expecte any significant accumulation below 10,000 ft. Mountain areas along and west of the Divide are under a Winter Storm Warning through Sunday monring for 5-10 inches of snow above 9000 ft, so travel through the mountains is likely to feature winter driving conditions today and tonight.

Severe weather is likely today across the Great Plains, with emphasis over the central Plains of NE, KS and OK where damaging tonadoes may be possible.

As upper trough passes through CO this evening, strong westerly winds are forecast to develop along the Front Range, with wind speeds of 20-45 mph and some higher gusts. Strong winds will persist into Sunday morning then diminish through the day on Sunday. Snow flurries will persist overnight tonight in the mountains above 9000 ft.

For Sunday, temps expected to remain slightly below seasonal norms, and showers and thunderstorms will develop over the High Country and move into the foothills and adjacent plains in the afternoon and evening hours. Coverage and intensity expected to be lighter than Saturday with snow level remaining above 10,000 ft.

For next week, models forecast another upper low to move into CA and then move across CO. Thus, showers and thunderstorms will develop Monday afternoon and evening, with activity persisting overnight in some areas. Expect heavy rain on Tuesday with severe thunderstorms also possible across eastern CO. Snow level could lower to 9000 ft Tuesday evening and night. As this system moves east, more diurnal showers and thunderstorms will develop Wednesday and Thursday with temps returning to near seaosnal norms. Then, another upper trough is expected to move across CO next weekend just in time for the Memorial Day weekend, so expected increased precip chances Friday through Monday with snow level remaning above 10,000 ft.

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

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

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Mostly clouds day today across CO as clouds ahead of a large upper low off the central CA coast move through. Showers developing along and west of the Divide, and some of these showers and isolated thunderstorms may move into the foothills and Urban Corridor late this afternoon and evening. Snow level should remain above 10,000 ft today.

Upper low is forecast to move into NV on Friday, and strong southwest winds aloft will move additional moisture into CO, thus better precip chances for most of CO west of I-25 on Friday. More favorable vertical shear profile will create a slight chance for some storms that move into eastern CO to approach severe limits Friday afternoon and evening. Snow level Friday should remain above 10,000 ft. As upper trough moves across CO Saturday, even better chances for precip statewide with some heavy rain possible. Showers and thunderstorms will be widespread with the possibility of some storms becoming severe mostly east of I-25 Saturday afternoon and evening. Snow level Saturday may drop down to 8500-9500 ft as colder air aloft moves over the state. Mountain areas above 9000 ft may see several inches of accumulation, with some accumulation in higher foothill areas as well. Temps will remain below seasonal norms on Saturday statewide.

On Sunday, we should start out mostly sunny, but clouds will build leading to a chance for afternoon and evening showers and thunderstorms, with best chances over higher terrain. Snow level should remain at or above 10,000 ft.

Next upper low/trough will move from southern CA across CO early next week. Thus, precip chances will remain high from Monday afternoon through Tuesday evening. Some areas could see some pretty heavy rains during this period, which will keep streams and rivers running at high levels. Snow level looks to remain at or above 10,000 ft during this period, but temps will remain at or below seasonal norms.

Wednesday and Thursday look to feature slightly warmer temps and lower precip chances, with activity mostly across the High Country. Then Friday through next Sunday precip chances look to increase once again as yet another upper low/trough moves from CA across CO, so could be a soggy Memorial Day weekend across much of CO. The good news is that open fires should not be an issue for those venturing out into the wilderness.

The latest ENSO outlook from the Climate prediction Center became available today. Positive ENSO conditions continue across the eastern Pacific, with the latest monthly value in the Nino 3.4 region of +1.0, indicating a medium strength El Nino conditions the past month. The 3 month average was +0.6 yileding a weak El Nino over the past 3 months. In addition, a positive MJO (Madden-Julian Oscillation) has been over western North America since mid April. I believe the combined conditions have caused our recent rainy period with a long wave upper trough over the western U.S. Indications from CPC indicate that the current El Nino is likely to intensify over the Summer and into Fall, with the potential of a strong El Nino by Fall. If this transpires, there may be implications for our CO weather. In general, a building or intensifying El Nino during our Summer months tends to enhance the North American Monsoon precipitation across CO, so we could see a continuation of above average precipitation through August and September. In addition, a medium to strong El Nino tends to favor above average snowfall for eastern CO during Fall months. We will have to wait and see how the current El Nino builds later this year, but it could also have positive implications for rainfall across CA this Fall and Winter, which is desperately needed.

Seasonal snowfall on Conifer Mountain now stands at 139.5 inches, which is 83% of our seasonal average of 168 inches. Despite our lower than average snowfall, our liquid precipitation is above average for this time of year, so from an overall moisture standpoint we are doing fine. Through May (from last September) our average precip is 9.36 inches, and we have received over 14 inches so far. Last year was the wettest year on record since 2006 with just over 23 inches for the 12 month period, so we still have a ways to go to catch that, but if we have a wet Monsoon, it is certainly possible. Our annual average precip is 17.6 inches on Conifer Mountain.

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

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

Bump for 5/16 update