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In Brief:
A vigorous short wave trough is passing to the north over the next couple of days . This will give us a small chance of afternoon storms and cool temperatures first to the lower 80'sF then upper 70'sF for the end of the week. We see highs climb back up to the mid and upper 80'sF - somewhat above average - temperatures next week. Dryness will be the overall rule.
3pm 9/10 Update:
The apology tour update: Note, a recent forecast called for quiet weather the rest of the week, but this short wave is looking quite strong and will impact northern Colorado more than appeared a few days ago.
Also, I mentioned that the GFS created a hurricane that hit around New York City later this week. That has vanished from the model, but it continues to create wandering storms around the Atlantic Basin and even in the Gulf over the next 2 weeks. Anything is possible, but long range hurricane forecasting is not a GFS strength. (It is entertaining to watch though <grin>.
Look for an earlier update tomorrow (Wednesday) to catch the details of the severe weather chances in the afternoon.
End 3pm 9/10 Update.
1:30 pm 9/10 Update:
The strong short wave will be doing "it's thing" tomorrow (Wednesday) with very large hail and supercells up in Nebraska. Areas just north of Denver and in the northern mountains of Colorado may see some of this severe thunderstorm activity with large hail as well. The SPC has issued a Marginal Risk for the Front Range with a Slight Risk and Enhanced Risk up in the northeast corner of the state.
End 1:30pm 9/10 Update.
Forecast Discussion:
Even though there is some surface moisture around, the bulk of the atmosphere over the state is really dry (red and oranges in Figure 1). The next trough is pretty dry and most of the energy is to the north of the state. As it approaches, we cool down and do see a chance of afternoon showers (Figure 2 and Figure 5).
The Longer Range Forecast:
The trough cools us the most on Thursday (Figure 3 and Figure 5) and things dry out (as far as rain chances go). We warm next week as the jet stream really flattens out (becomes zonal Figure 4). We stop seeing 'weather' for a while (Figure 5).
Taking a peak at our drought conditions, there are larger regions of abnormally dry and some regions of moderately dry (near the Four Corners area) forming. This is to be expected in the hot dry summer, but it is the most-moist I've seen the state at the end of summer since I've been watching it here. (Figure 6).
