Area Forecast Discussion
Issued by NWS Grand Rapids, MI
Issued by NWS Grand Rapids, MI
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504 FXUS63 KGRR 010535 AFDGRR Area Forecast Discussion National Weather Service Grand Rapids MI 135 AM EDT Sat Jun 1 2024 .KEY MESSAGES... - Showers/isolated storms Saturday/Sat night - Next decent chance of rain arrives later Monday - Strong storms possible Wednesday - Below normal temperatures for next weekend && .UPDATE... Issued at 1037 PM EDT Fri May 31 2024 One more quiet night before precipitation moves in Saturday afternoon. High pressure is centered in the Middle Atlantic states well off to our southeast, but ridging extends all the way back into the Great Lakes. The ridging will keep us dry through daybreak. Light southerly flow will develop tonight although moisture return will not occur until Saturday when dew points rise through the 50s. Increasing high clouds will thicken tonight with mostly cloudy skies by morning. Lows tonight should be in the 50s in most areas which is normal for this time of year. && .DISCUSSION... Issued at 248 PM EDT Fri May 31 2024 - Showers/Isolated storms Saturday/Sat Night Latest vis and ir loops show broken cirrus moving across the state as a weak wave aloft moves east. We won`t see any precipitation out of this tonight. However, precipitation is in the forecast Saturday. Sfc analysis shows a stationary front stretching from northwest WI southwest to eastern NE. Showers and storms have developed along the boundary but will remain west of the cwa tonight. That begins to change Saturday as low pressure over MO moves northeast toward Lower MI. Forecast soundings show a lot of dry air below 600 mb except for a narrow wedge near 820 mb. Some of the precipitation will go toward moistening the column and is the reason the models have been delaying the arrival of showers. Additionally, CAPE is meager so this should result in more showers than storms once the precipitation actually begins which should be after noon and perhaps as late as mid afternoon. Model blend has reduced PoPs a bit which makes sense given the dry air; higher PoPs will be over the southern cwa. The showers and isolated storms will slowly move east Saturday night, but may not totally clear the cwa by Sunday morning. - Next decent chance of rain arrives later Monday There may be some lingering showers/drizzle very early Sunday southeast of GRR before the shortwave fully departs, otherwise a dry day is expected with decreasing clouds. The next shortwave is shown to arrive from the west for Monday afternoon or night, bringing a period of higher pops for showers and possible storms. Only low chance pops look warranted at this time on Tuesday with mainly isolated pop-up diurnal convection expected in low shear environment. - Strong storms possible Wednesday Pops ramp up again on Wednesday with the approach of the next shortwave and strong cold front preceding the upper low approaching from the northwest. Its possible this could be an active severe weather day depending on degree of instability as deep layer shear will be on the increase. - Below normal temperatures for next weekend Pattern change comes in for the end of next week and next weekend as large upper low settles into the GrtLks Rgn. Still considerable spread in eventual position of the upper low and extent of the cool- down, but H8 temps as low as 2C arrive over the weekend. This would result in highs only in the 60s along with a daily shower risk. && .AVIATION /06Z TAFS THROUGH 06Z SUNDAY/... Issued at 135 AM EDT Sat Jun 1 2024 VFR conditions through Saturday morning then MVFR conditions overspread Lower Michigan from the south during the afternoon. Conditions will lower to IFR across southern Lower Michigan on Saturday evening as rain becomes more steady. Winds will be light and variable tonight then generally south and southeast less than 10 knots on Saturday. && .MARINE... Issued at 248 PM EDT Fri May 31 2024 High pressure over the Great Lakes will pose no hazards for small craft through Sunday night. Once the high moves east and the next frontal boundary approaches Monday, the pressure gradient will tighten and winds will increase; a Small Craft Advisory may be needed Monday. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...None. MARINE...None. && $$ UPDATE...Duke/04 DISCUSSION...Meade/04 AVIATION...Ostuno MARINE...04