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Forecast Discussion:
We had a few clouds move into NE Colorado in response to the low in the southwest today, but the sun was out and temperatures warmed (and snow melted). The main band of rain from this system is still over Texas (Figure 1).
We have a fun phenomena to explore today... that of an interesting way the upper level low (over Arizona) can dissipate rather than propagate (travel) somewhere. We'll start with the upper level map at 500mb (Figure 2). The low center (cut-off low) is plainly visible over Flagstaff. Aside from that low, there is a big ridge over the western half of the nation with a deep trough digging into the east (making them cold AND deflecting hurricanes).
By tomorrow (Figure 3) the low is fading out and being absorbed into the jet stream flow (as northwest flow begins to set up over the state. More in the longer range below...
The longer range forecast:
By Sunday (when we are at our warmest over the next 10 days - around 72°F) we have a southern portion of a big west coast ridge over the state. That low is gone. Another cut-off low is entering California (Figure 4).
Our next chance of rain (still small at this point) comes mid-week next week. Tuesday's upper-air map shows a trough approaching from the west again (Figure 5).
I thought I'd also feature the Weatherbell.com winter forecast (it is a great site, but its content is mostly behind a pay-wall; these are the public facing graphics only). They look at long range patterns and sea-surface temperature trends and the like to make their forecast. Figure 6 has unusual cold in the eastern and southeastern parts of the nation. We are just a bit colder than normal through February, if this is correct. Figure 7 is the snowfall potential/departure from normal. The southeastern U.S. will get a lot more snow than normal if this is correct. Longmont is near, or a touch below, normal snowfall.
