Area Forecast Discussion
Issued by NWS Denver/Boulder, CO
Issued by NWS Denver/Boulder, CO
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192 FXUS65 KBOU 012108 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 308 PM MDT Sat Jun 1 2024 .KEY MESSAGES... - Afternoon showers/thunderstorms today, strongest east of a line from Sterling to Limon where a few could become severe. - Still a chance of a couple severe storms Sunday over the northeast corner of the state - Summer heat through most of next week, with a few 90 degree readings over the plains. && .SHORT TERM /Through Sunday/... Issued at 222 PM MDT Sat Jun 1 2024 Dry line is currently a little west of a line from Sterling to Limon. The dry line will progress eastward through the rest of the afternoon and be east of the area by early evening. ML CAPE is expected to reach 2000 J/kg. This combined with 0-6km Bulk Shear of 35-40 knots should produce a few supercell thunderstorms. Large hail up to tennis ball size and damaging winds will be possible with these thunderstorms. To the west of the dry line, ML CAPE only reaches 500 J/kg. Dew points are falling into the 20s and 30s which will result in high-based showers and thunderstorms. Gusty outflow winds to 50 mph will be the main threat with these thunderstorms. The showers and storms come to an end this evening as the airmass stabilizes. For Sunday, a wave embedded in the westerly flow aloft will track across the region. At the surface, lee side trough will extend from far eastern Colorado north-northeast into South Dakota. Best lift from the passing wave will be over northern Colorado into Wyoming. Isolated high-based showers are expected to form over far northern Colorado. Eventually an organized outflow from the storms in Wyoming dives south and increases low level moisture which will bring a better chance for rainfall. Over the far northeast corner of Colorado where it will be more unstable, a severe storm or two will be possible. Airmass continues to warm Sunday, with highs across northeast Colorado expected to reach the mid to upper 80s. && .LONG TERM /Sunday night through Saturday/... Issued at 255 PM MDT Sat Jun 1 2024 Zonal flow is expected across the CWA Sunday night well into Monday, then a weak upper trough moves across Monday night into Tuesday. There is neutral synoptic scale energy over the CWA Sunday night with weak upward motion Monday through most of Monday night. Downward vertical velocity is progged on Tuesday. Looking at moisture, precipitable water values are progged in the 0.30 to 0.80 inch range Sunday night, then they increase into the 0.50 to 1.10 inch range Monday afternoon and night, then they decrease again Tuesday. For CAPE, models show values under 1,000 J/kg over the far northeast corner Sunday night. On Monday afternoon and evening there is limited CAPE, under 600 J/kg, over much of the CWA with slightly higher values over the far northeast corner. There is no CAPE progged on Tuesday. So for pops, will go with 10-30%s over the far northeast corner Sunday evening, then 10-20%s for the northern half of the CWA Monday afternoon and evening. That`s it. Temperatures stay above seasonal normals through the periods, with both Monday`s and Tuesday`s highs very closed to Sunday`s readings. The plains will see mid 80s to lower 90s both days for highs. For that later days, Wednesday through Saturday, models have upper ridging to dominate the weather for the forecast area into Friday. The center of an upper ridge is over southern Utah Wednesday, then central New Mexico on Thursday. By Friday, the upper ridge axis is pushed west and northwest of Colorado due to a strong upper low over the Great Lakes. By Saturday, the upper ridge axis moves back east towards and into Colorado. Moisture is sparse Wednesday, Thursday and Saturday, with a bit more progged on Friday. Overall, it will be dry and pretty warm with the only decent chance of showers and thunderstorms to be on Friday. && .AVIATION /18Z TAFS through 18Z Sunday/... Issued at 1131 AM MDT Sat Jun 1 2024 Light and variable winds are expected continue until showers and thunderstorms develop. The showers and storms in the Denver area are expected to be weak and high-based. Gusty outflow winds will occur with the convection with a few wind shifts expected for the Denver airports between 20Z and 01Z. Convection dies off after 01Z and winds slowly return to south/southwest drainage flow Saturday evening. For Sunday, VFR to prevail. Any shower/thunderstorm activity is expected to stay well north of the Denver area. West-northwest winds will increase after 18Z with gusts to 25 knots. && .HYDROLOGY... Issued at 255 PM MDT Sat Jun 1 2024 Alpine snowmelt will increase runoff the next few days. Hydrologic forecasts from the River Forecast Centers show a few streams getting to action stage by Monday or Tuesday, which means flows will be high and fast but flooding threat appears limited. Please use caution and respect these fast moving and cold flows in the high country. && .BOU WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...Meier LONG TERM....RJK AVIATION.....Meier HYDROLOGY....RJK/Barjenbruch