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000 
FXUS63 KGRR 230335
AFDGRR

Area Forecast Discussion
National Weather Service Grand Rapids MI
1135 PM EDT Mon Jul 22 2019

LATEST UPDATE...
Aviation

.SYNOPSIS...
Issued at 308 PM EDT Mon Jul 22 2019

-Comfortable conditions tonight!

-Chance of storms tomorrow afternoon

- Dry Wednesday through Friday

&&

.DISCUSSION...(This evening through next Monday)
Issued at 308 PM EDT Mon Jul 22 2019

Low pressure moving across Ohio is producing showers/storms south of 
the state. A well defined cirrus edge was noted from near Port Huron 
southwest to South Bend and its moving east. Diurnal cu was noted 
north of there across much of the cwa. This cu will dissipate toward 
sunset and wind will decrease. A very comfortable night is expected 
with dewpoints in the 40s and lows in the lower to mid 50s. 

The next chance of rain will be tomorrow afternoon. ECMWF and GFS 
show a short wave dropping south and NAMnest points toward scattered 
showers/storms east of US-131 after noon. H5 temps in the mid teens 
tomorrow afternoon will create moderately steep lapse rates. Given 
LI's near -7c and SBCAPE near 1200 j/kg, we could see some storms 
fire with lift generated by the short wave. Moisture may be a 
limiting factor though. However if the storms get going, a few 
hailers are possible, given the cold temps aloft; something to watch 
for. Behind the short wave, the upper ridge will start to move back 
in and we'll have a couple of days of dry weather Wednesday through 
Friday. Another cold front will drop south and give the northern cwa 
a chance for a storms, but chances are not all that high. The 
highest chance of rain will come Monday, if model timing is correct, 
which it probably isn't this far out. 

&&

.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
Issued at 1130 PM EDT Mon Jul 22 2019

VFR conditions will continue at all the terminals through late
Tuesday evening. Scattered showers will develop Tuesday afternoon
and linger into early Tuesday evening but conditions should remain
VFR at all the terminals. There is a very small chance for a
thunderstorm Tuesday afternoon and early evening but potential for
a storm is not enough to warrant inclusion in any of the terminal
forecasts. 

&&

.MARINE...
Issued at 308 PM EDT Mon Jul 22 2019

Lakeshore web cams show quite a bit of whitecap activity. Buoys 
confirm waves in the 3 to 5 foot range...3 ft closer to Ludington 
with the 4-5 ft waves south of Grand Haven. As the wind subsides 
tonight, the waves will decrease to less than 3 feet by morning. 


&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...Beach Hazards Statement until 6 AM EDT Tuesday for MIZ056-064-
     071.

     Lakeshore Flood Advisory until 6 AM EDT Tuesday for MIZ056-064-
     071.

LM...Small Craft Advisory until 6 AM EDT Tuesday for LMZ844>846.

&&

$$

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