Issue Date: Friday, June 4th, 2021
Issue Time: 8:30AM MDT

— Flooding is NOT expected today

No real changes in the atmospheric setup from yesterday, and a nearly cloud free start to our Friday. The High continues to strengthen to our southwest, which will again help to produce hot temperatures and mostly dry conditions across the state. Expect pulse-like storms to develop over the same areas as yesterday (southern high terrains) with residual, mid-level moisture, but perhaps with a little less coverage. Best chance for measurable rainfall will be south, along and near the Continental Divide. Decent storm motion to the NNW should also help limit accumulations and keep precipitation mainly confined the mountains. The main threat from storms this afternoon and evening will again be strong outflow winds as indicated by the higher DCAPE values from soundings this morning. DCAPE is a measurement of the sinking motion of an air parcel in a downdraft. So very strong, but brief outflow gusts will be possible with the stronger storms that develop this afternoon. Flooding is NOT forecast.

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:

Central Mountains, Southeast Mountains, San Juan Mountains, Front Range & San Luis Valley:

Scattered storms will develop again over the mountains this afternoon with best accumulation forecast along and near the Continental Divide. Isolated, brief max 1-hour rain rates up to 0.50 inches (southwest) and 0.20 inches (southeast) will be possible. A couple storms could spill into the San Luis Valley again, but more wind than rainfall is forecast. Further north (southern Front Range/Central Mountains), totals just under 0.10 inches will be possible again, but coverage will be less than yesterday. The main threat from storms that develop today will be lightning and brief, strong outflow winds. Flooding is NOT forecast today.

Primetime: 1PM to 10PM

Southwest Slope, Northwest Slope, Northern Mountains & Grand Valley:

Mercury levels are on the rise. Afternoon high temperatures over the Grand Valley will likely reach the 95F mark. Over the Northwest/Southwest Slope, highs will reach into the low 90Fs. Mountain valleys will reach the upper 70Fs, and 80Fs forecast for the transition zone from the Slopes to high terrains. Rainfall is not forecast. 

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

It will feel like summer this afternoon with clear skies and near 90F temperatures for the I-25 corridor and eastern plains. The Palmer and Raton Ridge will likely reach into the low to mid-80Fs. Rainfall is not forecast this afternoon. 

Issue Date: Thursday, June 3rd, 2021
Issue Time: 9:10AM MDT

— Flooding is NOT expected today

High temperatures will be on the rise today with the strengthening ridge overhead. As far as the first ingredient for rainfall, there’s a bit of mid-level moisture rotating around the High (mostly over the four-corners region). Average PW for that area was measured around 0.50 inches, which is plenty for scattered storms to develop this afternoon. Over Denver, PW was slightly higher at 0.58 inches, but a dry mid-level atmosphere was noted. For lift, there’s some weak mid-level energy moving around the High from north to south. Those weak disturbances and the daily diurnal flow will provide the lift for storm development over the mountains. Finally, instability looks to be decent over the central and southern mountains as well as over the eastern plains. However, NNE steering flow and lack of lift over the plains means that the scattered storms this afternoon and evening should be confined to the central and southern mountains. Further north (Front Range/Central Mountains), that dry air in the mid-levels should keep storms confined to areas along and close to the Continental Divide.

Morning soundings (south) indicated that the majority of the moisture today is located in the mid-levels. This and inverted-V profiles with decent CAPE imply that the main threat from storms that develop this afternoon and evening will be strong outflow winds. Accompanying those stronger, scattered storms that develop will be lightning, small hail and brief, heavy rainfall. Storms should dissipate quickly with the decreasing instability after the sun sets. Flooding is NOT forecast 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:

Central Mountains, Southeast Mountains, San Juan Mountains, Front Range & San Luis Valley:

Scattered storms will develop this afternoon over the mountains favoring areas south for more widespread development. Best coverage for scattered storms will be over the San Juan Mountains. The main threat from storms that develop south will be strong outflow winds, lightning, small hail and brief rainfall. Max 1-hour rain rates up to 0.50 inches (San Juans), 0.25 inches (Southeast Mountains) and 0.20 inches (Front Range and Central Mountains) will be possible. With NNE steering flow, some storms may wander into the SLV, but should dissipate rather quickly due to the dry surface layer. Flooding is NOT forecast today.

Primetime: Noon to 10PM

Southwest Slope, Northwest Slope, Northern Mountains & Grand Valley:

It’s going to be hot and dry today. Afternoon highs over the Grand Valley will reach into the mid-90Fs. With upper 80Fs and low 90Fs for the lower elevations of the Southwest and Northwest Slopes. Over the Northern Mountains, valleys should reach around 80F this afternoon. Rainfall is not forecast. 

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

High temperatures this afternoon will craw into the upper 80Fs with slightly lower temperatures for the elevated Ridges. There may be a few clouds this afternoon, but mainly looking at clear, blue skies. Rainfall is not forecast.

Issue Date: Wednesday, June 2, 2021
Issue Time: 9:00AM MDT

— Flooding is NOT expected today

The atmosphere above Colorado remains in somewhat of a holding pattern today. A very strong ridge, causing record high temperatures west of us, is strengthening but will still remain too far west to completely shut down storm activity. Meanwhile, moisture, as measured by PW, remains unimpressive but enough to cause isolated to scattered storm activity. PW at Grand Junction and Denver measured 0.51 and 0.48 inches, respectively, which is fairly close to seasonal normal for early June in Grand Junction and a bit drier than normal at Denver. Compared to yesterday, today will see (1) little to no organized disturbance overhead, (2) warmer mid-level temperatures by 2-4F, (3) less instability and (4) reduced shear. Overall, we expect a reduction in precipitation coverage, along with a reduced chance of severe weather. However, we still expect to see scattered showers and thunderstorms developing mainly over the higher terrain early this afternoon and this evening. Storms will have a hard time forming at lower elevations today, compared to yesterday. Short pulses of moderate to perhaps briefly heavy rainfall will be possible, but 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:

Front Range, Northern Mountains, Central Mountains, San Juan Mountains and Southeast Mountains:

Warmer with scattered showers and weak thunderstorms developing early afternoon and persisting into the early evening hours. Max 1-hour rainfall up to 0.5 inches (north) and 0.7 inches (south, especially along NM border) possible, along with some small hail in stronger storms. Flooding is NOT expected today.

Primetime: 12PM through 8PM

Northeast Plains, Southeast Plains, Palmer Ridge, Raton Ridge, Urban Corridor, San Luis Valley, Grand Valley, Southwest Slope and Northwest Slope:

Warmer and mostly sunny with an isolated shower or perhaps weak storm possible this afternoon and evening. Max 1-hour rainfall up to 0.5 inches. Flooding is NOT expected today.

Primetime: 1PM through 7PM

Issue Date: Monday, June 1, 2021
Issue Time: 9:45AM MDT

— Flooding is NOT expected today

As shown in the visible satellite image, below, the trough responsible for a long period of unsettled weather for Colorado is finally moving east. A strong ridge, currently centered over the Great Basin, is itching to move into its place. However, before that occurs, another disturbance will ripple through the northwesterly flow aloft today, providing scattered showers and thunderstorms mainly over eastern Colorado. This morning’s PW at Denver and Grand Junction was 0.34 and 0.40 inches, respectively. While this is certainly nothing to write home about, there was actually notably moister air to the north in association with the aforementioned disturbance. Thus, PW will rebound into the 0.6-0.9 inch range east of the Continental Divide this afternoon. This, coupled with the strong morning heating, will cause showers and storms that are capable of short-term heavy rainfall but not much more. With a strong increase in northerly steering winds aloft, to the tune of 40mph+, storm motion will be too quick to warrant a flood threat. However, severe weather in the form of large hail and damaging winds, will be possible with the strongest storms this afternoon over eastern Colorado. 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:

Northeast Plains, Southeast Plains:

Much warmer with scattered to numerous showers and thunderstorms this afternoon. Large hail and damaging winds will be possible with the strongest storms. Max 1-hour rainfall up to 1.4 inches possible, locally, especially along the KS border. However, flooding is NOT expected today. Note that storms could continue into the late evening hours along the KS and OK borders.

Primetime: 12PM through 12AM

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

Much warmer with scattered showers and weak thunderstorms this afternoon. Large hail and damaging winds will be possible over eastern areas. Max 1-hour rainfall up to 0.7 inches. Flooding is NOT expected today.

Primetime: 12PM through 7PM

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

Partly cloudy and pleasant today with isolated to widely scattered showers and storms possible this afternoon, mainly over the higher terrain. Max 1-hour rainfall up to 0.4 inches. Flooding is NOT expected today.

Primetime: 12PM through 6PM