FXUS63 KBIS 181747 AFDBIS Area Forecast Discussion National Weather Service Bismarck ND 1247 PM CDT Sat Apr 18 2026 .KEY MESSAGES... - Continued below average temperatures for today, along with gusty winds and scattered rain and snow showers (20 to 40 percent chance) this afternoon and early evening. - Temperatures trend warmer through this weekend and into the middle of next week, along with mainly dry weather conditions. - Active weather pattern is then favored after Wednesday of next week, along with a cooling trend into next weekend. && .UPDATE... Issued at 1247 PM CDT Sat Apr 18 2026 Diurnal cu is starting to develop in northwestern North Dakota. This will likely lead to rain and/or snow shower activity beginning within the next couple hours as forcing and mid-level moisture increases. Based on model forecast soundings, brief yet very strong winds are possible with any rain or snow showers that develop. UPDATE Issued at 837 AM CDT Sat Apr 18 2026 The forecast remains on track. UPDATE Issued at 627 AM CDT Sat Apr 18 2026 No major changes with this product issuance. See below for further details. && .DISCUSSION... Issued at 415 AM CDT Sat Apr 18 2026 Currently, strong northwest flow aloft with a long wave upper trough axis just to our east. Unseasonably cold temperatures early this morning, with most sites in the teens and low 20s. A few sites out west are actually only a few degrees from setting record lows for this calendar date! Warming trend starts today, with daytime temperatures 10-15 degrees warmer compared to Friday, with highs in the upper 30s to upper 40s. Within the northwest flow aloft, models depict a fairly well-defined embedded wave diving southward out of Canada and across the region today, along with left-exit region jet forcing moving over a strong baroclinic zone in place across the Dakotas. This forcing will coincide with several hundred J/KG of MUCAPE to result in diurnally driven scattered rain/snow showers from late morning through early this evening most areas. Another breezy day as well, with still 25-30 knots within the mixed layer available as we warm. Shower activity would likely help in bringing some of the stronger winds to the surface. Northwest flow aloft on Sunday transitions to more quasi-zonal Monday and Tuesday, ramping up the warming trend and resulting in a dry weather forecast. Warmest day will be on Wednesday, when broad ridging amplifies over the Northern Plains ahead of a strong upper level trough developing into the western CONUS. Ahead of this trough, a lee side surface low quickly spins up on Wednesday, increasing southerly flow and WAA into the region. High temperatures into the lower 80s across the south are forecast. As south-southwest flow aloft develops and increases Wed into Wed night, shower and thunderstorm chances will increase over the Dakotas. Latest NBM/WPC doesn't have thunder in the forecast, but would anticipate this being added if current trends hold. An active and cooler weather pattern continues to be favored for the end of the work week and into next weekend, with highs in the 40s and chances for snow mixing with rain returning to the forecast. && .AVIATION /18Z TAFS THROUGH 18Z SUNDAY/... Issued at 1247 PM CDT Sat Apr 18 2026 Generally speaking, VFR ceilings and visibility are expected through the period. However, isolated to scattered rain and/or snow showers are expected to develop this afternoon and pass from northwest to southeast into the evening hours before dissipating. Northwest winds of 15 to 20 kts with gusts up to 30 kts are expected this afternoon. However, much stronger gusts are possible with any showers that may occur. With incoming high pressure, expect winds to rapidly diminish and skies to clear this evening and overnight. && .BIS WATCHES/WARNINGS/ADVISORIES... None. && $$ UPDATE...Telken DISCUSSION...NH AVIATION...Telken