FTB 09-23-2022: Much Drier & An Uptick In Temperature 

Issue Date: Friday, September 23rd, 2022
Issue Time: 9AM MDT

— Flooding is NOT expected today

Only a narrow band of subtropical moisture can be seen in the water vapor imagery below (green arrow). As the Low to our north progresses eastward throughout the morning, rising heights behind the Low and building High pressure to our south will help to cut off the plume. Drier westerly flow has already moved over most of the state, and PW at Grand Junction has plummeted to 0.56 inches. Drying has also begun over the adjacent plains of eastern Colorado as witnessed by a PW value of 0.45 inches at Platteville. The ongoing westerly and northwesterly flow aloft should continue to scour out the remaining moisture over the far eastern plains, which is causing some fog and cloud cover this morning. With subsidence and advection of a drier air mass into the state, little to no rainfall is expected today. Best chance for an isolated, weak shower will be over the southern San Juan and Southeast Mountains, but with only light accumulations possible, flooding is NOT expected. The rising heights and drier air are also expected to produce warmer temperatures today. The hottest temperatures this afternoon should be located over the southeast corner, closest to the High.

Today’s Flood Threat Map

For more information on today’s flood threat, see the map below. If there is a threat, hover over the threat areas for more details, and click on burn areas to learn more about them. For Zone-Specific forecasts, scroll below the threat map.

Zone-Specific Forecasts:

Southeast Mountains, San Juan Mountains, Central Mountains, Northwest Slope, Grand Valley, Northern Mountains, San Luis Valley & Southwest Slope:

Best chance for an isolated storm or two today will be over the southern San Juan and Southeast Mountains where a little moisture may be able to hang on. If showers develop, high bases mean only light rainfall would be possible. Max 30-minute rain rates should remain under 0.1 inches, so flooding is NOT expected.

Primetime: 2PM to 7PM

Front Range, Urban Corridor, Raton Ridge, Southeast Plains, Northeast Plains & Palmer Ridge:

Warm and dry weather is forecast today. The fog and cloud cover over the plains should burn off by late morning. A high-based shower or two may try to develop along the Continental Divide over the southern Front Range, but more virga than meaningful rainfall is expected.