Issue Date: Tuesday, September 6th, 2022
Issue Time: 8:30AM MDT

— Flooding is NOT expected today

The anomalously strong High pressure center will continue to spin over Utah today, which will bring another day of hot and nearly dry conditions to the state. The clear skies shown in the visible satellite imagery below are a testament to the dry air and subsidence from the High. PW at Grand Junction has dropped to 0.37 inches, and it was measured around a half inch at Platteville. So, it’s quite dry with very limited surface moisture available. Some slightly higher moisture values are located over the southwest corner of the state, so isolated showers and weak thunderstorms may be possible over the San Juan Mountains. Outside of isolated, high-based mountain storms, rainfall is not expected.

Also shown in the image below are smoke plumes from fires across the western US. With persistent northerly flow around the High, the near surface smoke is expected to increase today over northwest and portions of west-central Colorado. Smoke aloft is expected to continue over the eastern plains, which may cause hazy conditions. 

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:

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

Best chance for high-based showers or weak thunderstorms will be along and near the southern portion of the Continental Divide (Central/San Juan Mountains). Isolated max 1-hour rain rates up to 0.4 inches may be possible (south) with most storms producing totals under 0.2 inches. So, flooding is NOT expected, and stronger storms may produce some brief gusts. Afternoon high temperatures will be close to yesterday, so very hot, with increasing smoke anticipated from the north.

Primetime: 3:30PM to 9PM 

Front Range, Southeast Mountains, Raton Ridge, San Luis Valley, Urban Corridor, Palmer Ridge, Northeast Plains & Southeast Plains:

It’s going to be another scorcher today with high 90s °F and a couple century readings forecast across the lower elevations. Mountain valleys will reach into the 80s °F again. Subsidence and drier air will keep precipitation chances close to zero, but some afternoon cumulus clouds are expected over the mountains. Flooding is NOT expected.

Issue Date: Monday, September 5th, 2022
Issue Time: 9:50 AM MDT

— Flooding is NOT expected today

The position of the upper level high-pressure remains unchanged from its location over the Utah and Nevada border since yesterday, and as a result the predominant northerly flow pattern continues across Colorado today. This morning, PW values of 0.6 and 0.48 inches were measured in Grand Junction and Platteville, respectively, indicating a slight moistening through the column west, with little change east. However, surface moisture has decreased across most of the state since yesterday, with dew points in the upper 20s to mid-30s°F common west and low 40s to low 50s° east. A weak disturbance moving through the flow is expected to trigger widely scattered storms across portions of southwestern Colorado this afternoon. However, subsidence associated with the ridge to the west and forecast limited instability in the range of 400-700 J/kg of CAPE should yield only low-intensity storms with light rainfall. Large dewpoint depressions should keep these storms confined to higher elevations southwest producing mainly virga showers. Additionally, faster steering speeds should keep storms moving to the southwest fairly quickly and further decrease rain rates. The remainder of the state is expected to remain dry, and near-record high temperatures are forecast across Colorado this afternoon. There is NO flooding expected today.

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: 

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

Skies are mostly clear and temperatures are currently warm across the western half of the state this morning. Near-record temperatures from the mid and upper-90s°F to low triple digits are forecast this afternoon. By mid-afternoon, isolated to widely scattered storms are expected to move southwestward across the southwestern Central Mountains, San Juan Mountains, and Southwest Slope. Given subsidence, limited instability, and a dry boundary layer, max 30-minute rain rates up to 0.2 inches may be possible, but mainly virga showers and gusty winds are expected. NO flooding is expected today.

Primetime: 3PM to 9PM

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

Clear skies continue for eastern Colorado this morning, with near-record temperatures in the mid to upper 90s°F forecast this afternoon. Weak upper-level dynamics should keep storm activity limited to the southwestern portion of the state, while eastern Colorado is expected to remain dry and very hot this afternoon. NO flooding is expected today.

Issue Date: Sunday, September 4th, 2022
Issue Time: 9:45 AM MDT

— Flooding is NOT expected today

The position of the upper-level high-pressure center has shifted back toward the western Utah border with eastern Nevada as of this morning, as shown in the water vapor image below. Increasing subsidence from the High is expected to have an even greater influence in terms of storm suppression than prior days, yielding forecast temperatures several degrees above climatological average across Colorado today. Very dry conditions are predominant across the state with respect to both column and boundary layer moisture as well. PW values of 0.51 and 0.49 inches were measured in Grand Junction and Platteville this morning, respectively. Meanwhile, dew points in the 30s°F and 40s°F were common west of the Continental Divide, with low to mid-50s°F dew points commonly found east. Notably, with upper-level dynamics having exited the state yesterday, there is negligible forcing or uplift to trigger storm development today. Daytime heating circulations over the mountains later in the day may spawn a few cumuli or a light virga shower or two across higher elevations in southern Colorado. However, no meaningful precipitation is forecast, therefore NO flooding is expected today.

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:

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

Clear skies throughout the day will allow for ample daytime heating that should warm temperatures to several degrees above average today. High dewpoint depressions and negligible moisture at the surface and aloft should yield dry and hot conditions this afternoon. A few stray cumuli and perhaps an isolated virga shower or two may drift across the mountains in southwest Colorado late this afternoon. No meaningful precipitation is forecast, and NO flooding is expected today.

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

Today, expect clear skies and temperatures several degrees above average for eastern Colorado. A few cumuli and perhaps a stray light virga shower or two may drift across the Southeast Mountains this afternoon. However, due to the negligible moisture and upper-level dynamics, no meaningful precipitation is forecast and NO flooding is expected today.

Issue Date: Saturday, September 3rd, 2022
Issue Time: 9:45 AM MDT

— Flooding is NOT expected today

The shortwave and surface boundary associated with a Mesoscale Convective Vortex (MCV) that was responsible for overnight and early morning storms is pushing south out of the state this morning. This feature is marked by an “X” in the water vapor image below, while the blue and white colors display the associated cloud cover and light showers over the southern Southeast Plains this morning. With the southward departure of the shortwave and surface boundary, clearing and warming can be expected across the state. Column moisture is lacking statewide as indicated by PW values of 0.46 and 0.64 inches measured in Grand Junction and Platteville this morning, respectively. Additionally, boundary layer moisture is very minimal across the western portions of the state, while mid-40s to upper 50s°F dew points are common across eastern Colorado.

By this afternoon, scattered storms are expected to develop along and west of the Continental Divide. The highest rainfall rainfall chances should be confined to the higher elevations of southwest Colorado where instability values may reach up to 500 to 800 J/kg of CAPE this afternoon. Given forecast quicker steering flow and a relatively dry boundary layer, virga showers and gusty winds are the most likely threats with these storms. However, if dew points in the mid and upper 40s°F can be reached over southwest Colorado, isolated brief heavy downpours will be possible. Meanwhile, eastern Colorado should remain dry after this morning’s weak showers depart the southern border counties. Flooding is NOT expected today.

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:

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

Light showers are departing the southern border counties this morning, otherwise skies are mostly clear across western Colorado. By this afternoon, scattered storm development is likely across the Central and San Juan Mountains, as well as portions of the Southwest Slope and the San Luis Valley. Given the forecast relatively dry boundary layer, these storms should mostly be virga showers producing gusty winds. Some isolated heavy downpours are possible primarily over the San Juan Mountains and eastern Southwest Slope where isolated max 1-hour rain rates up to 0.75 inches are possible. Over the Central Mountains, 1-hour rain rates up to 0.6 inches are possible. Flooding is NOT expected today.

Primetime: 1PM to 10PM

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

A few light showers and associated cloud cover over the southern border counties are exiting the state this morning, with clearer skies north. This afternoon, a few isolated storms may be possible over the Southeast Mountains and southern Front Range, but given limited instability and moisture, any storms that do form will likely be virga showers producing gusty winds. Isolated max 1-hour rain rates up to 0.4 inches will be possible with a storm or two that may occur over the Southeast Mountains and southern Front Range. Flooding is NOT expected today.

Primetime: 2PM to 8PM