Area Forecast Discussion
Issued by NWS Bismarck, ND
Issued by NWS Bismarck, ND
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444 FXUS63 KBIS 301806 AFDBIS Area Forecast Discussion National Weather Service Bismarck ND 106 PM CDT Tue Apr 30 2024 .KEY MESSAGES... - Widespread rain showers are expected to move across the state from west to east through the day. A rumble or two of thunder is possible. - Windy across southwest North Dakota today, with critical fire weather conditions expected in the afternoon and early evening. A Red Flag Warning has been issued. - Daily chances (low to medium) for rain (and maybe an isolated thunderstorm or two) through the rest of the week, with temperatures slightly below normal. && .UPDATE... Issued at 1240 PM CDT Tue Apr 30 2024 The Red Flag Warning was canceled for the southwest read the fire weather discussion for more information. Showers continue to push eastward across central North Dakota as a warm and cold front push across the region. Thunderstorms are possible across central North Dakota this afternoon as instability increases. Windy conditions are forecast this afternoon across the west as the low moves off to the east bringing in wrap around winds. Strong cold air advection will mix stronger winds aloft to the surface, but this will be a little to late to maximize the wind gusts. UPDATE Issued at 1005 AM CDT Tue Apr 30 2024 Rain showers continue to push eastward this morning. This trend will continue through the day, with some embedded thunderstorms at times. Breezy and dry conditions are still forecast in the southwest. There is some uncertainty to the extent of critical fire weather conditions as many areas in the southwest have received a tenth to a quarter of an inch of rain this morning. For now will monitor the amount of drying and wind behind the morning band of rain and maintain the current forecast. UPDATE Issued at 630 AM CDT Tue Apr 30 2024 We have seen some showers make their way into the far west and these radar echoes should become more and more widespread over the next few ours as the main upper level wave and cold front front moves in. Patchy dense fog (down to a quarter mile at times) has also become a bit more widespread this morning, mainly across northern areas and down into the James River Valley. We will go ahead and issue an SPS through 15z to account for this threat. Otherwise, no major changes were needed for this update. && .DISCUSSION... Issued at 425 AM CDT Tue Apr 30 2024 An upper level ridge axis will continue to move off to our east early this morning while western and central North Dakota settles into southwest flow aloft. A surface cold front is currently located near the Montana/North Dakota border and this boundary will cross this state from west to east this morning and afternoon. Widespread rain showers will accompany the cold frontal passage with radar returns now currently approaching the Montana/North Dakota border. Some of the CAMs have been aggressive in ramping this activity up in the 12 to 14 UTC time frame and beyond, even suggesting the potential for some embedded lightning strikes. That being said, instability will be limited as the RAP is only showing the potential for a couple hundred J/kg MUCAPE. Still, an embedded rumble of thunder or two isn`t out of the question and much of the forecast area has been highlighted in a general thunderstorm outline by the Storm Prediction Center. We will clear out rapidly late this morning and early afternoon across the west behind the front, especially the southwest where modest pressure rises and cold air advection will lead to some gusty west northwest winds. These winds will team up with the dry airmass behind the front to usher in some near critical to critical fire weather conditions across the southwest and portions of the south central. See the Fire Weather section below for more details. Most of the rain will move out to the northeast by late this evening. The heaviest totals continue to look probable across portions of the northwest and north central where the NBM is suggesting a 40 to 60 percent chance of a half inch of rain or more. The NBM suggests that almost all of western and central North Dakota has a 50 to 90 percent chance of a quarter inch of rain or more. The one exception will be across the far southwest and south central where probabilities drop off quickly. Most will see a break in rainfall on Wednesday but we could see some lingering showers across the far north. The next wave then rotates around the very slow moving upper low that will be centered near the Montana/North Dakota/Saskatchewan border by Wednesday night. We will then see our next round of low to medium rain shower chances Wednesday night through at least Friday, if not Saturday, as the upper low slowly moves across the region. Thursday looks to be the wettest day of the aforementioned period and the NBM suggests that much of the central and southeast could see a medium chance for another quarter inch of rain or more on Thursday. We will also start to see a bit more instability towards the middle to end of the week so some more isolated thunder will be possible as well. Regarding temperatures, we will see highs close to normal for this time of year on Wednesday, ranging from the upper 50s northwest to the mid 60s southeast. However, in the Thursday through Saturday time frame, we will be a bit cooler than normal with highs mainly in upper 40s to around 60. The NBM then suggests a return of highs in the mid 60s to lower 70s range by Sunday and Monday. That being said, considerable ensemble spread continues to be noted this far out. && .AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/... Issued at 1240 PM CDT Tue Apr 30 2024 A system continues to moves through the state resulting in rain across the region. Rain showers will lead to temporary MVFR conditions this afternoon. Thunderstorms are possible this afternoon, but confidence is low on location and timing. Winds are forecast to pick up across the west this afternoon as a front moves through the region. Skies will begin to clear west to east this evening as the system pushes eastward with winds diminishing by sunset. && .FIRE WEATHER... Issued at 1247 PM CDT Tue Apr 30 2024 The Red Flag Warning for the southwest was canceled due to a quarter inch of rain that fell this morning and cloudy conditions increasing minimum relative humidity. Cloudy conditions will also delay mixing delaying windy conditions. Windy conditions are still anticipated across the southwest later this afternoon. Thunderstorms are possible across the central half of the state this afternoon leading to gusty erratic winds. && .BIS WATCHES/WARNINGS/ADVISORIES... None. && $$ UPDATE...Johnson DISCUSSION...ZH AVIATION...Johnson FIRE WEATHER...Johnson