Area Forecast Discussion
Issued by NWS Grand Rapids, MI
Issued by NWS Grand Rapids, MI
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696 FXUS63 KGRR 151752 AFDGRR Area Forecast Discussion National Weather Service Grand Rapids MI 1252 PM EST Sat Nov 15 2025 .KEY MESSAGES... - Windy and 20 Percent Chance for Showers Today - Potential for Rain/Snow Mix Tuesday - Additional Rain Chances Toward the End of Next Week && .DISCUSSION... Issued at 239 AM EST Sat Nov 15 2025 - Windy and 20 Percent Chance for Showers Today High clouds are streaming overhead within the ridge axis. Lower clouds are expected to move in later this morning and afternoon as warm air advection 850mb low level jet convergence, and positive vorticity advection move in with the shortwave trough. The one limiting factor is moisture. Even with precipitable water values around 0.80 inches, soundings have a hard time becoming saturated as the shortwave moves through. Therefore PoPs are limited to 20 percent this morning and afternoon for light rain. However gusty winds are more likely during the afternoon and into tonight with the 30 to 40 knot winds aloft. We should start to mix some of these gusts down to the surface during the late morning and afternoon initially from the southwest then turning to the northwest during the afternoon and evening. Gusts of 30 to 40 mph are expected so make sure to secure any loose objects or decorations. With the northwest flow areas around US-10 and north could see some light lake effect showers. Lake Superior will be feeding moisture into the northern Lower Peninsula. Best chances (20 to 30 percent) for light snow will be in Clare County with the expected orientation of the bands. - Potential for Rain/Snow Mix Tuesday A weak mid level low will move from Colorado into the southern Great Lakes area Tuesday. A tight gradient of precipitation is expected along the low level warm air advection and frontogenesis. This is also seen in the low to mid level moisture fields. There are signals in the ensembles that this axis of precipitation could remain just south of the area, however there are still solutions that have the wintry mix across southwest Michigan. Therefore there are no adjustments to the NBM PoPs. If we see this axis of precipitation it will likely be snow initially then transition to rain as we lose cloud ice. There is a slight chance (20 percent) for a brief period of freezing rain Tuesday night before the rain ends. - Additional Rain Chances Toward the End of Next Week Looking at the cluster analysis a strong low pressure system is expected to move through the Great Lakes Region. There is a bit of uncertainty with the timing and track as seen in the varying cluster groups. There could be some instability to work with along with a strong low level jet. Overall the signal is there for wet weather late in the week especially with wind flow originating from the Gulf. We`ll just need to monitor the trends for the exact timing and where has the best chance for some rain. && .AVIATION /18Z TAFS THROUGH 18Z SUNDAY/... Issued at 1250 PM EST Sat Nov 15 2025 Gusty SW to W winds /20-30 kt/ early this afternoon will gradually veer to NW by late this afternoon and evening as a surface front/trough swings through the region. As previously noted, limited moisture is resulting in only a few very light showers along with a period of MVFR ceilings /2-3kft/. However, VFR conditions can be expected 19-21Z in the wake of the trough. Cold air advection and respectable pressure gradient will keep NW winds up through the night /generally sustained 10-15 kt with gusts to around 25 kt/. As cold air aloft continues to spill into the region late tonight, expect lower clouds to return, generally after daybreak /12-14Z/. Have tentatively kept cloud bases above 3kft /VFR/ but this will need to be monitored, especially over far western Lower MI given lake interactions. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...None. MARINE...Small Craft Advisory until 1 PM EST Monday for LMZ844>849. && $$ DISCUSSION...RAH AVIATION...Smith