FTB 09-14-2020: High and Dry with Some Smoke

Issue Date: Monday, September 14th, 2020
Issue Time: 09:25AM MDT

— Flooding is NOT expected today

Today will feel like déjà vu as we once again have mainly clear skies, a few mountain clouds, and temperatures only a couple degrees warmer than yesterday. Colorado is directly under a high pressure ridge today (see image below), which means there is very little upper-level winds and no large-scale driver of more interesting weather. Low-level moisture is not very strong, with dew points generally in the 30Fs over the mountain valleys, increasing to the 40Fs along the eastern Plains. This will be just enough moisture to allow clouds and a few showers to form over the San Juan and Central Mountains this afternoon as the abundant sunshine allows the atmosphere to bubble up some convection near mountaintops. Another slight bump in increased chances of showers exists for these regions today compared to yesterday, closer to 50/50 today for the San Juan Mountains. However, limited moisture and small convective cores will prevent any heavy rain accumulations. No flooding is expected today.

The true-color satellite image below shows that wildfire smoke from the West Coast is circulating around this high pressure ridge and has moved into northern Colorado. Some additional smoke is touching the southeast corner of the state. Fortunately, this appears to be upper-level smoke as air quality remains in the Good range for most locations across Colorado today. Smoke should stay limited over Colorado today, with the active Middle Fork and Cameron Peak fires in Colorado the likely source of most near-surface smoke. Hopefully the light winds will prevent any rapid fire growth today, though.

Today’s Flood Threat Map

For more information on today’s flood threat, see the map below. 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:

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

Daytime heating will once again allow clouds and some showers to develop over the high elevation mountain regions. The highest chances for seeing precipitation reaching the ground will be over the San Juan Mountains, where up to 0.15 inches of rain could accumulate over the day. Any showers should be small in size and remain over the higher terrain. No flooding is expected today. Temperatures will remain a few degrees above normal for valley locations and remain cool for high elevation locations, but the freezing level should remain above the highest mountaintops.

Primetime: 12PM to 8PM

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

Mainly sunny skies today, with some smoke potentially visible aloft for the northern parts of the state. Temperatures will be similar to yesterday or a few degrees warmer, especially along the northern half of the state where temperatures could get into the upper 80Fs. Generally light southerly winds can be expected, with gusts 15-20 mph possible as a surface low pressure develops well north of Colorado. No precipitation or flooding is expected today.