Area Forecast Discussion
Issued by NWS Grand Rapids, MI
Issued by NWS Grand Rapids, MI
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000 FXUS63 KGRR 160817 AFDGRR Area Forecast Discussion National Weather Service Grand Rapids MI 317 AM EST Sun Nov 16 2025 .KEY MESSAGES... - Cool and Breezy Today - Snow to Rain Late Monday Night into Tuesday - Additional Chances For Rain Wednesday Night into Friday && .DISCUSSION... Issued at 317 AM EST Sun Nov 16 2025 - Cool and Breezy Today Breezy conditions continue as northwest winds are expected to gust to 35 mph throughout the day. This is due to the stronger and colder air aloft that has moved in behind the cold front from yesterday. High temperatures will only be in the upper 30s to mid 40s today compared to yesterday`s 50s and 60s. With the colder air there is a 20 to 30 percent chance for lake effect showers to clip northwestern portions of Clare County. If winds shift more to the north this band could move further west into the county. Amounts are expected to remain under an inch with the probability of an inch or more only 10 percent. - Snow to Rain Late Monday Night into Tuesday Monday will be largely dry as we will be under subsidence and a dry air mass. Monday night a shortwave trough and associated vorticity maximum move from the Colorado area into the southern Great Lakes. A moisture gradient is likely to develop over the area with deeper moisture likely across southwest Lower Michigan. Looking at the moisture profile we`ll gradually saturate from top down, this will likely take time with the dry air mass in place. Looking at various solutions temperatures should be cold enough with the wet bulb effect for snow to start initially late Monday night into Tuesday morning, however as we go through the day we lose cloud ice and therefore are expected to see a transition to rain. Temperatures are marginal at the moment as to if there will be a freezing rain concern. Soil temperatures are still in the 40s and around 50 toward the I-94 corridor which should keep surfaces at or a few degrees warmer than the air temperature. Any accumulations are expected to be light with the marginal temperatures. The probability of a half inch or more is only 20 percent. - Additional Chances For Rain Wednesday Night into Friday Later into the week there remains some uncertainty with details in the forecast. A weak shortwave trough may cause some showers to develop Wednesday night (20 percent chance). Otherwise attention turns to Thursday and Friday. As mentioned before the cluster analysis shows various solutions in how the trough to the north phases with the trough from the southwest. This impacts timing, precipitation location, and amounts. However there is higher confidence with the warmer temperatures that precipitation type will be rain and we could even see a few rumbles of thunder. With moisture originating from the gulf we`ll also need to keep an eye on the heavy rain potential. Currently there is a 20 percent chance for 2 inches or more in southwest Lower Michigan. && .AVIATION /06Z TAFS THROUGH 06Z MONDAY/... Issued at 1143 PM EST Sat Nov 15 2025 Surface low pressure will gradually move eastward over the next 24 hours from the Eastern Great Lakes at present (05z Sun) to off the east coast of the U.S. by this time Sunday evening (05z Mon). High pressure will remain anchored in the Northern Plains. Southwest Lower Michigan will see a persistent northwest flow in between these two features. Progressively colder air will move into the region on the northwest winds which will generate clouds off of Lake Michigan. VFR weather is expected to persist through the forecast period of 06z to 06z. Moisture is very shallow, so we are not expecting precipitation at the TAF sites. We will see a mixture of ceilings around 6,000 feet the remainder of the night combined with cirrus with cloud bases at or above 20,000 feet. Towards morning, or around 12z, we should see cloud bases become more driven by lake effect processes. Cloud bases will lower to around 4,000 feet which will become fairly prevalent on Sunday. The main feature of note will be a northwest wind tonight that will generally be in the 08-20 knot range. On Sunday, after 13z, winds will ramp up to 14-30 knots. Wind directions will be fairly steady state in the 290-320 degree range. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...None. MARINE...Small Craft Advisory until 1 PM EST Monday for LMZ844>849. && $$ DISCUSSION...RAH AVIATION...Duke