Area Forecast Discussion
Issued by NWS Great Falls, MT
Issued by NWS Great Falls, MT
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440 FXUS65 KTFX 092025 AFDTFX Area Forecast Discussion National Weather Service Great Falls MT 225 PM MDT Thu May 9 2024 .SYNOPSIS... Expect clearing skies over the area this evening, as drier air moves in from the west. Additionally, warmer air will gradually move into North Central and Southwest MT starting tomorrow, with the warming trend continuing through the weekend. There is a small chance for showers in the Havre area on Saturday night, otherwise it is looking like Monday is the next chance for a bit more widespread shower or thunderstorm activity. && .DISCUSSION... Tonight through Sunday...An upper level ridge is trying to build in from our west. This is resulting in drier air slowly moving into the CWA. Thus most showers this afternoon will diminish by early this evening, with clearing skies in many areas this evening. Some patchy fog is possible by morning, especially over North Central MT. Warmer air will move into the CWA each day from Friday through Sunday, with Sunday looking to be the warmest day for most. Generally dry conditions are expected Fri/Sat, but a weak upper level disturbance will slide southeast from Canada into the Havre area on Saturday night into Sunday. This disturbance could produce a few light showers in the Havre/Harlem areas as the disturbance moves through. Monday through Wednesday...The weather pattern becomes a bit more active early next week, with areas of surface low pressure moving across southern Canada. This will result in scattered showers and thunderstorms moving through the CWA at times for the first half of next week. With the main area of low pressure to our north, widespread heavy precipitation is not expected over the CWA at this time. Afternoon temperatures will cool slight, but still generally be above normal for most areas. Brusda && .AVIATION... 1215 PM MDT Thu May 9 2024 (09/18Z TAF Period) Note: The NWS Great Falls Weather Forecast Office manages the following TAFs: KCTB, KHVR, KGTF, KLWT, KHLN, KBZN, KEKS and KWYS. VFR conditions prevail for the duration of this TAF period for most of our airfields. The exceptions are: KGTF - MVFR conditions are forecast, intermittently, for the first hour this TAF period due to low ceiling; KLWT - MVFR conditions are predominant until 09/23Z, due to low ceiling; and KBZN - MVFR conditions through 09/22Z due to predominant low ceiling. Patchy areas of fog/mist are forecast during the overnight period, tonight. Visibility through mountain valleys and passes may be poor, due to fog. Mountain obscuration should be expected, especially through this afternoon. Generally, light to breezy northwesterly to northeasterly winds are forecast. - Fogleman Refer to weather.gov/zlc for more detailed regional aviation weather and hazard information. && .HYDROLOGY... The flood warning will continue for Clear Creek. The water is receding on the creek, but it will just take a bit more time before the water levels go below flood stage. The areal flood advisory has been replaced with a flood watch for small streams and creeks that flow out of the Bears Paw Mountains this weekend. In talking with emergency managers in this area this morning, most creeks have receded from the recent rainfall. However, warm temperatures are expected to develop on Friday and then continue through the weekend. This could result in small streams and creeks that flow out of the Bears Paw Mountains to come out of their banks once again. Thus a flood watch has been issued for this area for that potential. Additionally, with warm temperatures expected elsewhere over the CWA from Friday through Sunday, expect small streams and creeks that flow out of the mountains of the remainder of North Central and Southwest MT to begin to rise as well. Since many of these streams and creeks are at lower levels, the threat/impact from any flooding that could develop is lower at this time. Never the less, we will continue to monitor the situation and should the potential for flooding increase elsewhere over the CWA additional flood statements might need to be issued over the weekend. Brusda && .PRELIMINARY POINT TEMPS/POPS... GTF 35 67 41 75 / 0 0 0 0 CTB 33 71 44 75 / 0 0 0 0 HLN 37 70 43 78 / 0 0 0 0 BZN 32 63 35 73 / 20 0 0 0 WYS 27 61 28 67 / 20 0 0 0 DLN 34 66 38 73 / 0 0 0 0 HVR 39 71 45 78 / 0 0 0 0 LWT 33 62 38 68 / 0 0 0 0 && .TFX WATCHES/WARNINGS/ADVISORIES... Flood Watch from Friday afternoon through Sunday morning for Bears Paw Mountains and Southern Blaine. && $$ http://www.weather.gov/greatfalls