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Area forecast discussion 
National Weather Service Grand Rapids Michigan
719 am EDT Monday Sep 22 2014

Latest update...

issued at 302 am EDT Monday Sep 22 2014

Skies should clear across the area by late morning. After that
skies will remain mostly clear through next weekend. Temperatures
will start out below normal today but warm to above normal by middle
week and continue that way through this coming weekend.


Short term...(today through wednesday)
issued at 302 am EDT Monday Sep 22 2014

Once the polar jet core moves east of the area by late morning
skies will clear and remain so for some time to come.

We start out with an extended east Asian jet around 45 north that
extends from near Japan to almost the west cost of the United
States (00z monday). Over time this breaks down into three
separate upper waves... all over the Pacific Ocean. That results
in split flow and ridging over most of the Continental U.S.. this pattern
will be very slow to break down. So expect mostly clear skies and
light winds with slowly warming temperatures starting this

Long term...(wednesday night through sunday)
issued at 302 am EDT Monday Sep 22 2014

The stretch of dry and quiet weather will continue into the extended
periods. Surface high pressure will drift over the eastern Great
Lakes by middle week...but then it retrogrades and builds back over
lower Michigan by the end of the work week as upper ridging also
strengthens over the region. Then by the weekend the upper ridge
and surface high drifts east again. This will produce a deeper
southern flow and temperatures should be warmer into the weekend. The core
of the upper ridge is over US on Saturday when a few areas may see
highs around 80...which will be about 10 degrees above normal.


Aviation...(for the 12z tafs through 12z Tuesday morning)
issued at 718 am EDT Monday Sep 22 2014

The low clouds continue to clear from northwest to southeast
leaving only jxn and lan with an overcast. Jxn was still MVFR
while lan was VFR as of 11z. All locations should be clear to scattered
by 15z. Model sounding suggest a cumulus cloud deck near 4000 feet
today so I put that in the taf forecasts. Expect clear skies and
light winds at all taf sites tonight. It is not out of the
question there could be some light fog toward Tuesday morning.
Later forecast will have to address that issue.


issued at 302 am EDT Monday Sep 22 2014

I continued the Small Craft Advisory till noon to allow the wave
heights to come down below 4 feet. The south third of our near
shore will be last place for this to happen.


issued at 302 am EDT Monday Sep 22 2014

With no rain forecast and rivers well withing their banks...
little to worry about here.


GRR watches/warnings/advisories...
Lm...Small Craft Advisory until noon EDT today for lmz844>849.



short term...wdm
long term...jk

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