FTB 06-10-2019: Limited Afternoon Rainfall with a Rebound in High Temperatures

Issue Date: Monday, June 10th, 2019
Issue Time: 8:45AM MDT

–A LOW flood threat continues for portions of the San Antonio/Conejos Rivers and for the headwaters of the Rio Grande and San Juan Rivers including the Rio Grande near Del Norte.

Mid and upper level flow over the state today will remain westerly, which will hold a dry air mass in place and limit afternoon rainfall activity. Expect the upper flow to transition to the northwest early tonight as the high to our south moves to the west and a ridge builds over the Pacific Northwest. The sounding in Denver this morning shows a large dry layer in the middle and upper atmosphere and an inversion, which are the main factor limiting the chance for afternoon rainfall. With low level moisture expected to mix out over the majority of the state, expect only partially cloudy skies this afternoon. The exception is over the southern Front Range and Southeast Mountain where slightly increased dew points (40°Fs) from surface southerly flow, diurnal flow and energy rotating the high in New Mexico will help sparked isolated showers and weak thunderstorms this afternoon. Storms are expected to move west initially and then have more southeast movement as the flow changes over. With the high-bases, the main threats will be gusty winds, small hail and lightning. Expect storms to begin dissipate at sundown as instability decreases.

High temperatures will also be on the rise after a cool Sunday. This will continue to melt snow at the higher elevations over southwest Colorado, so the Flood Watch for the San Juan Mountains and San Luis Valley continues. A Low flood threat has also been issued for portions of the San Antonio and Conejos Rivers, Rio Grande River (especially near Del Norte) and for all headwaters of the San Juan River and Rio Grande. I have pulled the Low threat into west in Mineral County due to reports of minor flooding along William Creek upstream from Lake San Cristobal.

Today’s Flood Threat Map

For more information on today’s flood threat, see the map below. For Zone-Specific forecasts, scroll below the map.

Flood Threat Legend

Zone-Specific Forecasts:

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

Expect high temperatures to jump back up 5-10°F from yesterday. Cloud cover will begin to build over the high terrains this afternoon, but rainfall is only forecast for the Southern Front Range, Palmer Ridge, Southeast Mountains, Raton Ridge and adjacent eastern plains this afternoon. Max 1-hr rain rates up to 0.6 inches are possible near the Divide with rates dropping to 0.15 inches/hour over the adjacent plains. There is a slight chance for some storms over the eastern San Juan Mountains, which may cause some light rainfall over the San Luis Valley as well. Totals are expected to remain under 0.2 inches (mountains) and 0.1 inches (San Luis Valley). Flooding is not forecast and rain rates near the Spring Creek burn scar should remain under threat criteria. As always, caution should be taken with any thunderstorm that moves over that area.

Increased flows over the Arkansas west of Pueblo will also be monitored closely over the next week as a couple of gages have jumped to the Action stage. Not expecting any of these gages to reach the minor flooding mark this week. Please tune into your local NWS office for the latest on flood warnings, advisories and statements and follow the daily FTB.

Primetime: 3PM to 9:30PM

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

With dew points in the 20°Fs over the northwest corner, not expecting rainfall this afternoon. There will be an increase in cloud cover by mid-afternoon, but rainfall will be limited to the southern mountains where there is slightly better low level moisture. Warm temperatures will continue the melting of the high elevation snow. The Flood Watch continues for the San Juan Mountains and San Luis Valley. A Low flood threat has also been issued for portions of the San Antonio and Conejos Rivers, Rio Grande River (especially near Del Norte) and for all headwaters of the San Juan River and Rio Grande. Areal Flood Advisories (as of this morning) are issued for the following: Central Hinsdale County above Lake San Cristobal along Williams Creek, Colorado River near the CO/UT state line, Animas River near Durango, San Juan River at Pagosa Springs, La Plata River at Hesperus, Manco River near Mancos and the Gunnison River above Grand Junction. Follow the NWS for the latest updates on the daily runoff and river stages.