Pops of fall color along Pass Creek – Pic taken 9/25/2023
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Wednesday – 27 Sep 2023 – 9:00am
The past…
At Stevens Field the high temperature yesterday was 75 and the low this morning was 38. Humidity bottomed out yesterday afternoon at 14%.
The peak wind at Stevens Field yesterday was 18mph.
| Average High | Record High / Year | Average Low | Record Low / Year |
| 70 | 82 / 1963 | 32 | 13 / 1993 |
Precipitation summary… There was no measurable precip reported in the last 24 hours.
Fire updates…
Quartz Ridge Fire link
Bear Creek Fire link
Forecast discussion…
We “weather guessers” call spring and fall “transition seasons”. During autumn in the northern hemisphere, nights are longer than days, temperature contrasts get wider between the southern and northern latitudes, and the polar front jetstream gets more active. Weather models struggle during the transition seasons. I’m definitely seeing this struggle with a low pressure system that could impact us this weekend. Some models expect a few raindrops for us, while some expect a soaking. The one thing they agree on is that it will get windy. Details are in my forecast below.
There is nothing on radar in our area this morning.
Forecast Highlights…
*** Lots of blue sky and pleasant fall temps through Friday. ***
*** More clouds, scattered showers, and breezy this weekend. ***
*** Cold spots in valley will flirt with freezing temps each morning this week. ***
Today through Friday… High pressure is in control. We’ll see lots of blue sky, no precip, and pleasant temps. Thursday and Friday the ridge will shift to our east so we’ll see a few more clouds and slightly stronger afternoon winds.
Winds… Winds each morning will be light and variable. Beginning around 11am each day winds will increase into the 10-20mph range out of the southwest. Thursday and Friday afternoon winds will increase into the 15-25mph range.
Temps… Highs will be in the low to high 70s and lows will be in the mid-30s to mid-40s. The cold spots will flirt with lows near freezing each morning.
Saturday and Sunday… A deep low pressure system will dip down into the Great Basin. I expect the best moisture and storm energy to stay to our west and northwest. We’ll see more clouds, scattered showers, and gusty winds.
Snow levels… Will start at 12,000ft Saturday afternoon and drop to 10,500ft by Monday morning. I expect 1-3” of snow above 11,500ft and up to an inch down to 10,500ft.
Winds… Saturday afternoon gusts will be in the 25-30mph range. Sunday afternoon gusts will be in the 30-35mph range. Gusts in the mountains will be in the 40-50mph range.
Temps… Saturday highs will be in the high 60s to mid-70s and lows will be in the mid-30s to low 40s. Sunday highs will be in the low to high 60s and lows will be in the low 30s to low 40s.
On the top left, the NBM expects 0.14” for Pagosa. In the upper right, the Euro shows 0.31”. In the bottom left, the GFS shows 0.07”. In the bottom right, the Canadian model shows 1.03”. Hmmm – what to forecast? This is typical during transition season and leads to low forecast confidence. For now, I’m leaning toward the NBM, but I see potential for more precip. Monday morning I’ll verify these models against what actually happened. Verification is a constant part of the forecast process.
First the Euro… All 50 versions expect precip – good for forecast confidence. However, amounts range from 0.10” to 2.2” – a big difference not good for forecast confidence. 21 out of the 50 versions expect over 1”.
And the GFS… All 30 versions expect precip but the timing varies considerably – low forecast confidence. Amounts range from a trace to 0.80” – a narrower difference but still considerable – low forecast confidence. Zero of the 30 versions expect over 1” – huge difference compared to the Euro.
Conclusion: This system is just 4-5 days out and the models are all over the place. One model expects hardly anything while the other expects a good soaking. At this point, I expect most of us to get 0.15” to 0.30”. Hopefully these models will come together with a solution in the next few days!
My next post will be on Friday.
– Shawn
