Area Forecast Discussion
Issued by NWS Grand Rapids, MI
Issued by NWS Grand Rapids, MI
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985 FXUS63 KGRR 171059 AFDGRR Area Forecast Discussion National Weather Service Grand Rapids MI 659 AM EDT Fri May 17 2024 .KEY MESSAGES... - Isolated showers and storms today - Dry tonight and milder Saturday - Warm and dry weekend - Showers/storms Monday-Wednesday && .DISCUSSION... Issued at 330 AM EDT Fri May 17 2024 - Isolated showers and storms today An upper level shortwave is bringing a few showers and storms to our nw fcst area early this morning and isolated showers also clipping our extreme se fcst area. We expect this pcpn to taper off toward daybreak with dry wx for the vast majority of our fcst area today. However with a cold front moving slowly through our area we expect a few showers and isolated storms to redevelop mainly this afternoon over our eastern fcst area. In fact 00Z HREF guidance suggests sb/mu capes will reach around 1000 j/kg this aftn just ahead of the front. However potential for stronger or organized convection is mitigated significantly by weak shear. No severe weather is expected today. - Dry tonight and milder Saturday Fair wx is fcst tonight through Saturday as weak sfc ridging builds in. Some patchy fog is expected late tonight through mid morning Saturday. Ample sun and southerly waa along with h8 temps reaching around 14-15 C will result in high temps Saturday reaching the lower to perhaps middle 80s across most of our area. The weak sfc gradient will be conducive to lake breeze development which will keep temps near the Lake MI shoreline considerably cooler. - Warm and dry weekend Upper ridging will develop over the weekend leading to very warm temperatures by Sunday. H8 temps climb to around 14c leading to highs in the mid 80s. A weak cold front moving across northern Lower will probably not have enough energy to produce precipitation over the northern cwa, but it may lower dewpoints enough to result in some elevated fire weather concerns Sunday afternoon along the northern tier of counties. - Showers/storms Monday-Wednesday A cold front will slowly move toward the Great Lakes Monday ahead of a high amplitude upper trough. For several days the models have been advertising showers and thunderstorms developing along the front. Monday, this precipitation will be generally west of the cwa, but may see some convection drift over the western cwa during the afternoon. The better and stronger setup arrives Tuesday as we see a stronger surface low develop in the southern Plains and move northeastward across Wisconsin. Strong southerly flow ahead of the low will send moisture into the cwa and short waves rotating through the upper trough will help in firing convection. Once again the latest models suggest fairly robust values for SBCAPE, bulk shear, and EHI. This points toward the potential for convective organization Tuesday and a potential severe threat. Another warm day is expected Monday with highs in the mid 80s, but once clouds/showers/storms move across the cwa Tuesday, temperatures will fall back into the 70s. && .AVIATION /06Z TAFS THROUGH 06Z SATURDAY/... Issued at 657 AM EDT Fri May 17 2024 Patchy dense fog exists across the region, but will burn off during the next few hours. VFR expected through 06z and then some MVFR/IFR fog will develop again overnight tonight. && .MARINE... Issued at 330 AM EDT Fri May 17 2024 No wind or higher wave hazards are expected across our nearshore waters in the near term. Wind speeds through the weekend will be fairly light. Some patchy fog is possible early this morning and then again tonight. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...None. MARINE...None. && $$ DISCUSSION...Laurens/04 AVIATION...04 MARINE...Laurens