Area Forecast Discussion
Issued by NWS Grand Forks, ND
Issued by NWS Grand Forks, ND
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041 FXUS63 KFGF 280318 AFDFGF Area Forecast Discussion National Weather Service Grand Forks ND 1018 PM CDT Mon May 27 2024 .KEY MESSAGES... - Another round of showers and thunderstorms arrives Thursday into Thursday night, with a 50% chance for more than 0.50 inches over this 48 hour period && .UPDATE... Issued at 1018 PM CDT Mon May 27 2024 There is still just enough elevated instability/marginal mid level lapse rates with the passing shortwave trough that additional light showers (and a few lighting strikes) are moving through the region, with a more definitive end to rain behind the mid level trough axis. Instability should continue to diminish through midnight and what forcing is there should move to the southeast, but for now I adjusted PoPs/Wx to account for a slower end to rain/thunder northwest to southeast. UPDATE Issued at 658 PM CDT Mon May 27 2024 RAP analysis already shows a decrease in low level lapse rates and as the sun sets this should continue with MLCAPE rapidly decreasing. Limited elevated instability/marginal mid level lapse rates may still support a few lingering lighter showers beyond sunset, but the bulk of activity should end by 03Z. The had be a few marginal updrafts that supported smaller hail and a few gusts in the last few hours but this threat has also started to wan as shallower updrafts reflect decreasing instability trends. && .DISCUSSION... Issued at 256 PM CDT Mon May 27 2024 Another interesting day with boundaries and shortwaves pushing through the FA. The first shortwave pushed south and east of the FA by early afternoon, and it is now affecting south central Minnesota. There is also a scattered line of showers and storms from Devils Lake to Garrison to Watford City. This area saw a little more sun today, so it has squeaked out about 500J/kg of MLCAPE, but weak effective shear. Finally a secondary shortwave was located over southern Manitoba, which will move across the FA tonight into Tuesday morning. After this last shortwave moves through there should finally be a couple of dry days as 500mb ridging moves back in. As this ridge pushes east, rain chances return again for Thursday and Thursday night, and possibly Friday night into Saturday morning. The regional radar clearly shows the activity around each of the areas mentioned above. This activity is fairly scattered (30-50% coverage) and will likely hang around well into the evening. Model guidance is indicating another batch of lower clouds dropping from southern Manitoba into the northern FA around sunrise Tuesday. This area continues to slide southward through the morning, as it slowly thins. This, along with fairly steady northwest winds in the 5 to 10 mph range should prevent much fog from forming. There should be more sun around by Wednesday, but temperatures may only struggle to get back to normal (around 70F). As mentioned above, the next round of rainfall will move from west to east across the FA Thursday into Friday morning. This has been pretty well advertised in the ensemble solutions. The more notable change today is that there may well be a break in the precipitation after this initial line of precipitation moves through. Therefore, eastern North Dakota could dry out again Thursday evening, and areas east of the Red River could too on Friday. However, so far anticipated precipitation amounts shouldn`t deviate too much from the mention above (50% chance for more than 0.50 inches over a 48 hour period). Behind this, there could be another wave for Friday night into Saturday morning. && .AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/... Issued at 658 PM CDT Mon May 27 2024 Several areas of showers are moving across eastern ND and northwest MN, with coverage already starting to decrease west to east. There is still a low chance for a few light showers overnight, but chances will be too low to linger mention beyond 03Z. Under some of these showers in the afternoon/early evening ceilings have dropped to 3000 FT AGL, but this is transitioning east with the main activity and VFR should prevail through 11Z once the current activity ends. There is still a strong signal for more widespread MVFR (localized IFR) stratus to arrive in the 11-14Z period northwest to southeast Tuesday morning, overspreading eastern ND and northwest MN as surface high pressure builds into the region. Improvement back to VFR is favored by midday as daytime heating/mixing increases. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...None. MN...None. && $$ UPDATE...DJR DISCUSSION...Godon AVIATION...DJR