Area Forecast Discussion
Issued by NWS Pocatello, ID
Issued by NWS Pocatello, ID
798 FXUS65 KPIH 130846 AFDPIH Area Forecast Discussion National Weather Service Pocatello ID 246 AM MDT Thu Jun 13 2024 .SHORT TERM...Today through Friday night. Expect no impacts today with mainly sunny skies and minimal winds. A weak wave will bring isolated showers and thunderstorms tonight and Friday mainly in the Upper Snake River Highlands in the Centennial Mountains mainly near the Wyoming and Montana borders. Very little precipitation expected. A weak frontal passage will increase winds on Friday as well. Expect 15 to 25 mph sustained winds Friday afternoon in the Snake River Plain with the strongest over the Arco and Mud Lake regions. Temperatures will be very mild today with highs in the upper 80s to lower 90s in the Snake Plain and most low elevation sites with 70s to lower 80s in high elevations. Expect slight cooling Friday with highs mainly in the 70s mountains and 80s valleys. Friday will begin a cooling trend. GK .LONG TERM...Sat through Wed night. A trough entering the northern Rockies and Great Basin will increase wind strongly, to where Wind Advisories may be needed for the Snake River plain and eastern Magic Valley, for sure at least a Lake Wind Advisory for the American Falls Reservoir. Wind will continue breezy to windy on Sun and Mon, then fall to normal to breezy on Tue and Wed. Should stay mainly out of the southwest and west, although with the cold front passage on Sat there may be a temporary shift to northwest. The incoming cold front appears to be quite dry with little chance of any precipitation. This upper level low, even as an open wave, moves slowly, and actually closes off on Mon directly overhead. The cold core of the low does go all the way to the surface. Low PoPs develop Sun night, with Mon and Tue reaching borderline likely PoPs on the northern end of the forecast area, and slight chance level PoPs at the ID-UT border. Wed has diminishing PoPs as the low starts to lift to the northeast for some of the clusters, leaving us dry. Right now, it`s a 50-50 probability split. The cold front makes temperatures for Sat afternoon cool considerably, from mid-80s in the Snake River plain Fri to mid-70s in the same place Sat; which is below normal for the time of year. By Sun, afternoon temperatures will struggle to reach 70 degrees F. Mon continues the cooling trend, with highs in the central Idaho mountains in the 40s and 50s mostly, and 60s in the Snake River plain. Tuesday is even 2 to 4 degree colder for the highs. A warming trend should arrive on Wed. Messick && .AVIATION...Some mid-level moisture will slide through the westerly flow today, mostly between the 10000ft AGL and 14000ft AGL altitudes. So do not expect any precipitation. Cloud cover should reach BKN at KBYI and KPIH, possibly KSUN, while KIDA and KDIJ should stay at FEW-SCT cloud coverage. Wind is much less today compared to the winds of the last 4 days. No impacts on VSBY. Messick && .FIRE WEATHER...The hottest day of the next seven is today, with BLM land elevations reaching the 90s in the TFD and southern portions of the IFD. Afternoon humidity should get below 15 percent in a lot of low elevations in the central Idaho mountains and the northwest side of the two main BLM districts. An approaching trough that arrives on the weekend with a cold front will start affecting weather on Fri. While today wind will be light, on Fri the wind will spike upwards again, with the strongest wind occurring on Sat. Strong cooling brings back temperatures more like early to middle spring on Mon and Tue. Messick && .HYDROLOGY... A flood warning remains in effect for the Teton River at Driggs through Saturday. The Snake River at Heise is near flood stage and the Snake at Lorenzo also rising. GK && .PIH WATCHES/WARNINGS/ADVISORIES... None. && $$