wxgeek's weather-Update Monday April 11

Update Mon Apr 11

Storm system that moved east of us now causing a batch of severe weather across the Midwest, specifically the lower Mississippi and Ohio Rievr Valleys, with tornado watches across a large area. This is a reminder that severe weather season is not far off for us in CO. May and June usually bring us our majority of severe weather.

Very pleasant weather across all of CO today. A weak upper trough in southwest flow aloft will move across the state on Tuesday, and bring a chance for isolated showers Tuesday afternoon and evening, mostly over the High Country and north of I-70. There is a slight chance we could see an isolated shower over the foothills and Plains, and some could even become thunderstorms. Snow level woudl be above 10,000 ft but some hail or grauple is possible in heavier showers.

A more significant upper trough is then forecast to move across the state on Wednesday into Thursday. This system will begin to bring snow to the mountains west of the Divide during the day on Wednesday, and then bring a good chance for showers and steady precip across the foothills and Plains Wednesday night into Thursday morning. Snow level will be 7500-8500 ft Wednesday afternoon, lowering to 5500-6500 ft by Thursday morning. At this time, looks like any snow acumulation would be less than 2 inches across higher foothills. Eastern Plains could receive more moisture, but mostly in the form of rain. Some strong northwest winds are forecast to follow behind this system on Thursday afternoon and night into Friday morning.

For the weekend, a mixture of sun and clouds, with a chance for some isolated showers in the afternoon and evening. Snow level will be 9000-10,000 ft, but convective nature of showers may produce isolated thunderstorms with small hail and grauple. Showers are most likely over higher terrain.

On a brighter note, long range progs are now hinting at some significant moisture for next week Tuesday through Thursday, but will refrain from too much excitement until this is shown within 48 hours.

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Update Sat Apr 9

Today is on track to have higher fire danger than Friday, as southwest winds aloft increase to 40-65 mph bringing surface winds of 25-55 mph across a large area of the foothills and Plains. All of eastern CO is under a Red Flag Warning today. Another very tough day for local fire crews.

Upper low currently over LA will move northeast tonight and Sunday, but latest models have the track of this system even farther north now, which has almost taken away any precip chances we had. Snow will move into the western mountains today and tonight, with Winter Storm Warnings and Winter Weather Advisories posted for most areas west of the Divide. SW mountains will receive the brunt of this system, but travel across I-70 tonight and Sunday morning could be tough.

For the foothills, we may see a few snow showers early Sunday morning, but I doubt anywhere will get more than an inch of snow from this system, and many areas may see no snow at all or a dusting. Strong southwest winds from today will turn northwesterly after the front passs tonight, so cooler temps and blustry winds for Sunday, but very little moisture. More strong westerly winds on tap for Sunday night and Monday morning. The remainder of Monday and Tuesday look warmer with less wind.

Next system looks like it will bring a chance for precip from Wednesday into Thursday morning, but nothing significant.

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Update Fri Apr 8

Red Flag conditions will prevail today into Saturday afternoon. South to southwest winds currently in the 15-35 mph range across the foothills and Plains, and will likely increase this afternoon and evening, and may persist overnight and into Saturday afternoon. Wind speeds on Saturday may be higher than today as upper low moves into the AZ/CA border area. Humidities also dropping, currently at 25% at 9350 ft, and will likely drop below 15% later this afternoon and evening, as well as into Saturday afternoon.

Upper level low currently over central CA will move into SoCal tonight and then begin to move northeast over the weekend. Latest models fairly consistent and move the upper low into south central CO Sunday morning and then into northwest NE Sunday evening. This track is not ideal for snow in our foothills, as the flow at the surface and aloft remains northwesterly, so very limited if any upslope component is currently forecast. Snow will move into the western mountains Saturday afternoon, and cold front will move across eastern CO Saturday night. Winter Weather highlights are in effect for most mountain areas west of the Divide, and southwest mountains could receive significant snowfall Saturday into Sunday. Once cold front passes, winds will become northwesterly and temps will begin to drop. It does not appear that snow will begin until early Sunday morning and will be brief, with all shower activity ending by Sunday afternoon. At this time I would not expect more than 1-3 inches for most foothill locations, with many areas only receiving a dusting to a half inch. Snow level will begin quite high at 8000 ft at midnight Saturday night but lowering to Plains level by Sunday morning, so snow is possible over the Metro area Sunday morning, but likely less than an inch. Some areas farther east, especially north of I-70 could receive 1-2 inches of snow Sunday morning. The other impact will be very strong northwest winds developing behind the cold front as a surface low develops over northeast CO Sunnday morning. This will create very blustry cotnditions for most of the day on Sunday, and strong windns will continue into Sunday ncight, with speeds in the 25-40 mph range. Winds will cause blowing snow and reduced visibility in areas where it does snow.

Models indicating warmer and calmer conditions on Monday into Tuesday. Next chance for precip looks to be Wednesday/Thursday when an upper level trough moves across CO. Nothing significant looking to this time. In fact, long range models suggest a rather dry, breezy and warm pattern for most of April.

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Nice post frontal upslope flow very appreciated by fire flighting personnel today. A weak upper level trough will move across CO today which is bringing snow to the High Country west of the Divide, and will bring a chance for showers to the foothills and northeast Plains this evening and tonight. Snow level will be 9000-10,000 ft this afternoon lowering to around 8000 ft Thursday morning. Still not expecting more than an inch of accumulation in areas above 8000 ft overnight. Northeast Plains could receive a bit more rainfall though. Thursday will have similar conditions with a chance for afternoon showers across the foothills and Plains. Snow level 8500-9500 ft Thursday, and showers will be more convective in nature, so some areas could receive brief heavy showers, while other areas remain dry. Would not expect more than an inch of accumulation for most higher foothill areas, unless a heavy convective shower passes over which could drop 1-2 inches of snow in isolated areas.

Friday into Saturday morning will be bring scary fire weather conditions. Upper low will move down along the West Coast and will bring increased southwest flow aloft, which will translate to very strong southwest surface winds along the foothills in the 25-50 mph range. Temps will also rise, and humidities will be below 15% causing extreme fire danger. Most critical conditions will exist from noon Friday through noon Saturday. The West Coast upper low will track into SoCal on Saturday, and move into northeast NM by Sunday. Latest models in much better agreement, so confidence is increasing in the weekend forecast. The best chance for precip currently looks to be from Saturday afternoon into Sunday afternoon. Snow level will begin around 8000-9000 ft Saturday afternoon, lowering to 6000-7000 ft Sunday morning. This system will likely bring some much needed moisture, but it does not look like a significant system at this time. Potential amounts will be refined in coming days, but we're likely talking about a few inches of snow for the higher foothills.

Long range models indicate warmer and breezy conditions for Monday, then a chance for more precip Tuesday/Wednesday.

Bump for April 9 update

Bump for April 11 update