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In Brief:
We enjoy one more day in the 80'sF - then a vigorous cold front passes over Longmont around noon Friday. With it comes thunderstorms (not looking severe at this time). We cool about 20-30F degrees and may pick up 1- 1.50 inches of rainfall over the next 10 days.
Forecast Discussion:
For fun, now that we are hitting 80'sF down here, let's look at this snow-year in review (Figure 1). We are still quite a bit above average for the date (at least one ski resort is going to try to stay open until June). We are at 159% of normal snow pack with a statewide average at 14.6 inches of snow. Last year, on this date, we had about 1/3rd an inch of snow left over the state.
Today (Thursday) the next (really wet) storm is crashing into the west. Flooding has begun in California already (Figure 1). The mountains will wring out most of the moisture before it gets here. We will still hit the lower to mid 80'sF today (Figure 3) with a chance of an afternoon hit-or-miss thundershower moving off the mountains to the northeast.
The Longer Range Forecast:
The front arrives midday Friday with a good amount of precipitation and thunderstorm activity (Figure 3). Without enough moisture in place- the severe weather is expected to remain out on the Nebraska and Kansas border and eastward (Figure 4). We'll watch to see if this changes. The GFS shows the southwest to northeast storm tracks on Friday giving us between 0.25 and 0.5 inch of water (Figure 5). The weatherunderground.com model agrees with 0.25 inch of water.
The weatherunderground.com model gives us about 1.50 inches of water over the next 10 days (Figure 3) while the GFS (Figure 6) gives us 0.75 to 1 inch of water over these 10 days. We'll see if anything changes as the weekend approaches.