FXUS63 KBIS 230105 AFDBIS Area Forecast Discussion National Weather Service Bismarck ND 805 PM CDT Wed Apr 22 2026 .KEY MESSAGES... - Critical fire weather conditions across most of western and much of southern North Dakota this evening. - Isolated showers and thunderstorms from south central into eastern North Dakota this evening and tonight. A few of these could be on the stronger side with gusty winds. An isolated strong storm with gusty winds could also brush the far northwest this evening. - High chances of rain west and low to medium chances of rain central on Thursday, followed by low chances of wrap around showers, mostly in the form of snow, Thursday night through Saturday. - Strong west to northwest winds Thursday and Friday. && .UPDATE... Issued at 802 PM CDT Wed Apr 22 2026 Isolated showers with occasional lightning have developed from Lake Oahe through the northern James River Valley, and more recently as far north as the Turtle Mountains. A handful of wind gusts around 50 mph have been measured under and near this activity, but on a more consistent basis, peak gusts have been closer to 40 mph or less. A relatively stronger storm was poised to enter southern Emmons County as of 8 PM CDT. Attempts at convective initiation have been made in northwest North Dakota over the past couple hours, but only a couple of rain showers have been able to materialize with no lightning observed as of 8 PM CDT. Further south, an increase in synoptic scale winds has been observed early this evening throughout southwest North Dakota between a surface dryline and cold front. The Red Flag Warning may need to be extended in time for this part of the state. && .DISCUSSION... Issued at 112 PM CDT Wed Apr 22 2026 As of 1 PM winds across western ND were mainly in the 15 to 25 mph range, with humidities 25 to 35 percent. Wind directions were southerly over southwest ND to easterly over northwest ND. Across the south central winds were southeast at 15 to 25 mph with humidities around 35 to 40 percent. Additional Fire Weather info is contained in the Fire Weather Section. As the Montana surface low pushes into northeast Montana this afternoon, increasing moisture is being pulled northward from the central Plains. A modestly unstable, but capped atmosphere currently over eastern SD will continue to advect northward into eastern ND this evening, with a band of unstable air working all the way back west into northwest ND. These two areas (Northwest ND) and the far south central into the James River Valley are the focus for thunderstorm activity tonight. In the far south central and James River Valley, the atmosphere is expected to remain capped. However, with instability aloft and an increasing low level jet this evening, there could be some isolated to scattered elevated convection that lifts northeast through the area. With strong environmental winds in place A strong to marginally severe wind gust could mix down to the surface. Some small is also possible. In the northwest, very steep lapse rates have developed over eastern Montana. Isolated high based thunderstorms are possible this afternoon into the evening, mostly over eastern Montana, but there is a low threat that an isolated storm could brush the far west central into northwest ND, near the border. These storms would have the potential for winds gust to around 60 mph. On Thursday, the surface low lifts into southern Manitoba and we see strong wind develop over western North Dakota Thursday morning and eventually spread into central ND by late morning or afternoon. Bufkit soundings indicate there is 50 to 60 knots of wind at the top of the mixing layer. The question is if this can mix down to the surface. Some of our general guidance such as the ECMWF EFI are not real impressive with the winds Thursday, but certainly in the Advisory criteria in the west. The NAEFS SA pages does show a nice 850mb and 700mb jet into Far southwest ND around Midday Thursday. Guidance shows the surface low lifting north in the afternoon with the surface gradient relaxing a bit, so the confidence in strong winds advancing east through central ND is low at this time. If this did occur, it wouldn't be until Thursday afternoon and into the evening, therefore week did not extend the Wind Advisory through central ND and later shifts will have the chance to evaluate further. Except for any convection this evening, and morning wrap around showers in the northwest Thursday morning through mid afternoon, much of the day over most of the forecast area is expected to be dry. Much of the west and central is in the dry slot late tonight, and as the surface and upper low lifts north and wobbles back to the west into Saskatchewan, much of the state remains within an unfavorable position for any significant precipitation Thursday into Thursday night. Then as we get into late Thursday night through Friday night, the stacked now drops back south to along the International Border. This will keep some low precipitation chances to northern portions of the forecast area. By this time we are cool enough that they may fall as either rain or snow. However, any significant accumulations are not anticipated at this time. Saturday and Sunday into next week we see a slow gradual increase in temperatures with hit and miss precipitation chances. && .AVIATION /00Z TAFS THROUGH 00Z FRIDAY/... Issued at 802 PM CDT Wed Apr 22 2026 VFR conditions are expected through tonight. Isolated showers and thunderstorms are possible near KXWA this evening, and to the east of KBIS and KMOT into the overnight hours. The main hazard from showers and storms is erratic wind gusts. On Thursday morning, and area of rain with MVFR ceilings will move into western North Dakota. The rain is forecast to lift northeastward and diminish through the afternoon while MVFR ceilings persist in the west and expand into central North Dakota. Some snow could mix with the rain along the Montana border. Winds will remain gusty this evening through tonight, generally southwesterly to southerly around 10-20 kts. Low level wind shear will impact central and eastern North Dakota later this evening into the overnight hours. Westerly winds will become strong on Thursday, with sustained speeds around 25-35 kts and gusts up to 45 kts. && .FIRE WEATHER... Issued at 802 PM CDT Wed Apr 22 2026 Critical fire weather conditions continue across western and far southern North Dakota early this evening. The Red Flag Warning may need to be extended in time in the southwest. For Thursday, expect windy to very windy conditions out of the west before becoming northwest in the afternoon in western ND. Low rain chances are present across central North Dakota in the afternoon, with medium chances in the west and especially northwest. This will maintain relative humidity values in excess of 40 percent across most of the state. That said, lower values down to around 25 percent are possible mainly in the James River Valley. Winds in the James River Valley will be initially strong from the south, then shift southwest to west and increase later in the afternoon. near critical fire weather conditions are expected in the James River Valley due to the strong winds and low humdities. Should the wind shift be delayed, it's possible that Critical fire weather conditions could occur. Will need to monitor the far south central into the James River Valley Thursday for Critical Fire Weather conditions. && .BIS WATCHES/WARNINGS/ADVISORIES... Red Flag Warning until 9 PM CDT /8 PM MDT/ this evening for NDZ001-009-017>020-031>034-040>048-050-051. Wind Advisory from 7 AM CDT /6 AM MDT/ to 7 PM CDT /6 PM MDT/ Thursday for NDZ001-009-017-018-031>033-040-041-043-044. Wind Advisory from 11 AM CDT /10 AM MDT/ to 7 PM CDT /6 PM MDT/ Thursday for NDZ002-003-010-019-020-035-042-046-055>062. && $$ UPDATE...Hollan DISCUSSION...TWH AVIATION...Hollan FIRE WEATHER...TWH/Hollan