National Weather Service Raw Text Product

559 
FXUS63 KGRR 181830
AFDGRR

Area Forecast Discussion
National Weather Service Grand Rapids MI
230 PM EDT Fri Oct 18 2019

LATEST UPDATE...
Synopsis/Discussion/Marine

.SYNOPSIS...
Issued at 230 PM EDT Fri Oct 18 2019

- Warmer weekend.

- Potential prolonged wind event/large waves along the lake shore
  Mon night/Tue.

- Showers/storms Monday. 

&&

.DISCUSSION...(This evening through next Friday)
Issued at 230 PM EDT Fri Oct 18 2019

The weekend is going to be fairly quiet wrt weather. High pressure 
over Michigan will slowly move east and south winds will develop. 
Look for warmer temperatures to push north into SW Lower Saturday 
and even more so Sunday. We're looking at highs around 60 Saturday 
and mid 60s Sunday with plenty of sunshine filtered through high 
clouds. 

Another Fall storm is brewing, though, and will affect West Michigan 
Monday-Tuesday. Both the GFS and ECMWF have been fairly consistent 
in showing this strong storm. A significant piece of energy will dig 
southeast across the central Rockies and will induce a low to 
develop in the Plains. The mild air ahead of the low combined with 
the cold air behind it will produce a strong storm that will move 
toward western Lake Superior by late Monday. An occluded front will 
push through the cwa Monday. Ahead of it showers and thunderstorms 
will develop. The bigger story will probably be the fairly strong 
wind behind the front. ECMWF ensembles shows a 30-36 hr period of 
wind in the 30-45 mph range; a couple of the ensembles are around 50 
mph. The dense colder air behind the front will create large waves 
and we'll be likely looking at more beach erosion and perhaps some 
flooding along roads very close to the lake shore. As the low lifts 
north across Ontario, the wind will subside late Tuesday night and 
Wednesday. 

Another strong storm is possible late in the week. The ECMWF shows a 
storm similar to the Monday storm and a similar track, however, the 
GFS takes the storm south across the Ohio Valley. Highs for the 
latter part of the week are expected in the lower 50s. 

&&

.AVIATION...(For the 18Z TAFS through 18Z Saturday afternoon)
Issued at 113 PM EDT Fri Oct 18 2019

VFR conditions will continue through the evening and overnight TAF 
period with clear skies and fairly light winds. For Saturday we will 
begin to see southerly winds pick up mainly for lakeshore areas with 
wind gusts up to 20kts possible, especially for MKG. Otherwise 
expect no major weather impacts to terminals for the forecast period.


&&

.MARINE...
Issued at 230 PM EDT Fri Oct 18 2019

We issued a Small Craft Advisory north of Grand Haven for late 
tonight and Saturday. South wind will increase to 15 to 25 knots 
tonight which will push waves to 3 to 5 feet. Wind and waves will 
decrease late Saturday afternoon. 

Much stronger winds...most likely gales...will develop Monday behind 
a cold front and those strong winds will continue into Tuesday. 

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...None.
LM...Small Craft Advisory from 2 AM to 8 PM EDT Saturday for 
     LMZ847>849.

&&

$$

SYNOPSIS...04
DISCUSSION...04
AVIATION...Honor
MARINE...04