Issue Date: Saturday, June 4th, 2022
Issue Time: 10AM MDT
— A LOW flood threat has been issued for portions of the Northeast & Southeast Plains
Taking a look at the water vapor imagery below, yesterday’s disturbance has now moved east into Kansas and Nebraska (large orange “X”). Today, a negatively tilted trough will continue to persist to our west as a weak ridge begins to build overhead, which will help increase afternoon high temperatures statewide. Unlike yesterday, there is no strong mid-level disturbance that is expected to move through the flow during peak heating, which means storms that do develop this afternoon and evening over eastern Colorado should be more isolated in nature. The main mesoscale feature to highlight today is a surface Low that is forecast to develop over the Southeast Plains, which should setup a nice dry line.
As the dry line sets up, the green dashed line (marks high dew points) should begin to sharpen. Downsloping winds over the Southeast Mountains should help keep this forecast zone and the adjacent plains rain-free today, although it is possible that some moisture may hang on over the Kansas/Colorado border for an isolated storm over eastern Baca or Prowers County. On the north side of the surface Low, more easterly and southeasterly surface winds should help maintain the higher moisture values over the Northeast Plains. These two features are expected to set the stage for another round of rainfall to fire over the northern Front Range and Cheyenne Ridge, and to a lesser extent the eastern Palmer Ridge, this afternoon. As these isolated to widely scattered storms are steered east into the deeper moisture and greater instability, they should begin to intensify. A couple severe storms will be possible over the Northeast Plains, which would also be capable of producing isolated heavy rainfall in the moisture rich environment. Therefore, a Low flood threat has been issued.
Back to the west, PW at Grand Junction was measured at 0.39 inches with a very dry conditions noted from the surface up to 3km. This, along with increasing heights, mean the majority of western Colorado should remain dry and hot this afternoon. There may be some isolated, weak storms that develop over the Northern Mountains and Front Range with a little mid-level energy skirting the northern tier of the state and some residual moisture, but rain rates and coverage should stay well below flood threat criteria.
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, Urban Corridor, Palmer Ridge, Northeast Plains & Southeast Plains:
Isolated storms may develop this afternoon over the Northern Mountains and Front Range. Max 30-minute rain rates up to 0.20 inches will be possible, but coverage should be limited with most storms producing totals under 0.15 inches. Gusty winds may accompany the stronger storms that develop.
Over the northern Urban Corridor, isolated storms may produce up to 0.35 inches of rainfall. As storms move east, rain rates should increase with max 1-hour rain rates up 1.75 inches possible over the eastern plains. With several outflow boundaries likely in this area from yesterday’s rainfall, a storm may stall along the eastern border and produce locally high rainfall totals up to 3 inches. A Low flood threat has been issued for this area, but storms should be more isolated in coverage when compared to yesterday. Flood threats include road flooding, field ponding and rises in local creeks, especially if storms track over the same area as yesterday (saturated soils). A couple severe storms are also possible with the main threats being large hail and gusts up to 60mph. A isolated storm or two may develop further south in eastern Baca and Prowers County, depending on the location of the dry line, but it is more likely that the dry line sets up just east of the border. If these storms do develop over these areas, they should quickly move east, which will limit their flood threat.
Primetime: 12PM to 8PM (west); 4PM to 10PM (east)
San Luis Valley, Southeast Mountains, Raton Ridge, Central Mountains, Northwest Slope, Southwest Slope, Grand Valley & San Juan Mountains:
An isolated sprinkle or two may be possible over the San Juan and Central Mountains near the Continental Divide today. Otherwise, it should remain rain-free with high temperatures reaching up to 90F for the lower elevations, 80Fs for the SLV and mid to upper 70Fs for the mountain valleys. Flooding is NOT forecast. A Red Flag Warning has been issued for the SLV until 8PM tonight with west winds forecast in the 15 to 25 mph range and relative humidity dropping into the low teens.
