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822 FXUS65 KBOU 270836 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 236 AM MDT Wed May 27 2026 .KEY MESSAGES... - Expect widespread showers along with scattered thunderstorms today. A few spots may see locally heavy rainfall. There will be a limited risk of flash flooding in the burn scars. - Thursday will scattered showers and thunderstorms over the far northeast plains and in and near the foothills. - Thunderstorm chances will increase Friday through Saturday, across the plains, with a chance of severe thunderstorms especially on Saturday. - Thunderstorm chances may decrease on Sunday over the plains. && .DISCUSSION /Through Tuesday/... Issued at 226 AM MDT Wed May 27 2026 A weak upper level low/disturbance is over nern New Mexico early this morning and is fcst to lift slowly northeast into sern CO/swrn KS by tonight. This will result in decent coverage of showers and a few tstms over sern portions of the CWA thru this aftn. With SSE low level flow in the mid levels, some of this activity will spread NNW across the rest of the plains this aftn. Although precipitable water values will gradually increase up to an inch, SBCAPE is generally 500 j/kg or less. So the threat of stronger tstms appears to be on the low side although some spots may still receive locally heavy rain. Across the higher terrain, there will be a good chc of showers and tstms as well this aftn. Highs across the plains will be in the mid 60`s to mid 70`s with the warmest readings over nrn areas. For tonight, the weak upper level low is fcat to slowly move NNE across ern CO and wrn KS. As a result, this may alead to additional shower activity along with a few tstms over the far ern plains overnight. On Thu, the ECMWF has the weak upper level low over nwrn KS by midday while the GFS has it over far nern CO. With a blocking upper level high over the nrn Plains, more than likely this feature will move nearly do north. In the vicinity of the weak upper level low expect more showers thru at least midday over the far nern plains. Further to the west from the I-25 Corridor into the mtns there will be a chc of showers and tstms in the aftn. Depending on how much heating occurs SBCAPE may range from 500-800 j/kg. Thus may see a few stronger storms with locally heavy rainfall due to expected slow movement. As for highs, readings will stay in the 70`s over nern CO. Looking ahead to Fri, the blocking pattern of the nrn Plains will shift eastward as a storm system moves into the Great Basin. As a result, the flow aloft will become more SSW (albeit weak) with SE low level flow over the plains. Depending on how much heating occurs SBCAPE may reach 1500 j/kg over the plains in the aftn. Although Bulk Shear is rather weak still can`t rule out an isold svr storm or two from late aftn thru the early evening hours. Over the higher terrain, there will be a chc of higher based showers and storms. Meanwhile highs across the plains will range from the upper 70`s to mid 80`s. For Sat, the upper level low over the Great Basin will weaken and move into wrn WY with the flow aloft becoming more SW across the area. At the sfc, a lee trough will extend from sern WY into sern CO. Across the plains, SBCAPE will range from 1500-2000 j/kg by aftn with better Bulk Shear. Thus will likely see a few svr storms, across portions of the northeast plains in the aftn thru the early evening hours. Across the higher terrain, tstm chances will be on the low side as drier air spreads across. By Sun, the upper level low will be over the nrn Rockies with WSW flow aloft across the area. At the sfc, current data is showing lower level moisture decreasing on Sun across the plains. If that occurs then tstm chances would decrease. Over the higher terrain will keep in a slight chc of higher based showers and tstms. Looking ahead to Mon, the upper level low will still be over Montana with SW flow aloft across the area. Depending on how much low level moisture there is, over the plains, will determine tstm chances. Across the higher terrain there will be a slight chc of higher based showers and tstms. && .AVIATION /06Z TAFS through 06Z Thursday/... Issued at 1116 PM MDT Tue May 26 2026 SSE winds will be in place overnight and will continue thru Wed aftn. Only expect some mid and higher level cloud cover overnight but ceilings will drop down to around 6000 ft by 16z. By 19z, there will be a chance of showers along with a slight chc of -tsra thru the aftn hours. If a heavier shower or tstm were to occur ceilings may briefly drop down to 3500 ft. By 23z winds will become more SE and continue into Wed evening. There will continue to be a chc of showers with a slight chc of -tsra thru 04z. Ceilings will remain around 6000 ft. && .BOU WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...RPK AVIATION...RPK