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Forecast Discussion:
The stormy weekend rages on (well in the evenings at least). There are lows forming and moving on and reforming on the Plains, a stationary front that is draped down the Rockies and stretching east-west near the Palmer Divide or as far south as the Raton Plateau at times. This has cool, often foggy, drizzly weather in the northeastern part of the state, warm moist air down south and cool dry air out west (figure 1). Very interesting, and stagnant, pattern (as we saw with the upper air pattern halting and drifting a bit west over this time period before filling in).
Short waves coming down the stream (jet stream) are kicking off afternoon thunderstorms (when surface heating is at a maximum) giving us great thunderstorms Sunday PM and some small hail.
Figure 2 is the cell that moved by around 6:30pm Sunday. Figure 3 is a radar product that tries to tell the difference between rain, snow, hail and other combinations and types. The red colors are hail and rain mixed. Storms 'trained' (multiple cells passing over the same locations like boxcars on a train) over Longmont into the mid evening. Figure 4 is another cell at 7:45pm that hit us with pea sized hail around NE Longmont. I am at over 1.1 inches of rainfall since Thursday in NE Longmont, total.
Today, the situation repeats with fog/drizzle in the morning (easterly up slope flow) followed by thunderstorms in the afternoon. Figure 5 is the surface forecast for the morning. Figure 6 is the SPC thunderstorm forecast for the afternoon. We are under a marginal risk of severe weather again (small hail and strong winds and localized flooding are the risks).
The longer range forecast:
We warm a touch tomorrow but have another day with afternoon thunderstorms (and probably another marginal risk of severe weather issued as we get closer). We dry out a bit on Wednesday and Thursday then rain and thunderstorms return for Friday into the weekend. More later!
