892 FXUS63 KGRR 062342 AFDGRR Area Forecast Discussion National Weather Service Grand Rapids MI 742 PM EDT Wed Oct 6 2021 LATEST UPDATE... Aviation .SYNOPSIS... Issued at 327 PM EDT Wed Oct 6 2021 - Showers and storms tonight through Friday night - Period of warmer and drier weather Sat night into Sun night - Another chance for rain early next week && .DISCUSSION...(This evening through next Wednesday) Issued at 327 PM EDT Wed Oct 6 2021 - Showers and storms tonight through Friday night A fairly long period of southeast flow both at the surface and aloft is expected from tonight through Friday night. A moist regime will be in place...with surface dew points in the 60s...850mb dew points in the +10C to +12C range and precipitable water values of 1.5 to 1.7 inches. During this period an upper low will lift our direction from Missouri, as it does transitioning into an open wave. Best chances for precipitation will come Thursday night and Friday while the wave will be moving through our region. The precipitation will have a diurnal flare to it which is typical of upper low type systems. MUCAPE values will reach the 1,000-2,000 J/KG range during the afternoon's of both days and never really drop to zero even at night. So, a cloudy and showery period...with embedded storms especially during the afternoon. No severe weather is expected with generally lighter winds in place. Strongest storms would likely occur Friday afternoon/evening. - Period of warmer and drier weather Sat night into Sun night A period of warmer and drier weather is expected from as early as Saturday through Sunday night. So, essentially the weekend will feature warm and mainly dry weather. 850mb temperatures in both the GFS and the ECMWF rise to +18C over Grand Rapids this weekend. This is fairly warm for even mid summer let alone October 9th and 10th. We will likely have temperatures in the 80s this weekend for highs, especially on Sunday in our southern CWA at least. This stretch of warmer than normal weather is certainly noteworthy and the beat goes on. - Another chance for rain early next week Another upper low moves our direction form the plains on Monday and moves through our region Monday night into Tuesday. We will have showers in the forecast from Monday through Tuesday as this wave is working through. We have mainly showers in the forecast at this point, but could see the need to add more thunder as we get closer in time. The models are still showing above normal moisture in the profile for this time of year. && .AVIATION...(For the 00Z TAFS through 00Z Thursday evening) Issued at 742 PM EDT Wed Oct 6 2021 Areas of IFR can be expected overnight into Thursday morning. Showers will move in from the south on Thursday and some scattered thunderstorms are possible in the afternoon but this was left out of the forecast for now as coverage is expected to be low. East to southeast winds 10 knots or less through Thursday afternoon. && .MARINE... Issued at 327 PM EDT Wed Oct 6 2021 An off shore flow is expected tonight through Thursday night. Winds will generally be in the 5 to 15 knot range, but may occasionally nudge up into the 10 to 20 knot range. In either case, these are not Small Craft Advisory winds and waves will remain on the low side. Winds will be light southerly then for a time from Friday into Saturday. SCA conditions not expected during this time either. A signal remains in the models of stronger southerly flow setting up for Saturday into Sunday night. Winds and waves may reach SCA criteria during this time frame. So, if you have plans out on the water, better conditions are expected in terms of flatter water from now through Saturday morning. The latter half of the weekend may get bumpy, with winds possible hitting the 20-30 knot range. Waves could easily bump into the 4 to 6 foot range, possibly a bit higher. Gale force winds around 35 knots are noted at 1,000ft around Sunday at daybreak. Worst of the conditions will be likely on Sunday morning from Holland northward. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...None. LM...None. && $$ SYNOPSIS...Duke DISCUSSION...Duke AVIATION...Ostuno MARINE...Duke