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Area forecast discussion 
National Weather Service Grand Rapids Michigan
328 am EDT Tuesday Sep 2 2014

Latest update...
synopsis/short term/long term/Hydro/marine

issued at 328 am EDT Tuesday Sep 2 2014

An isolated shower or even a thunderstorm cannot be ruled out
today...but in generally most areas will remain dry. High pressure
will provide dry weather tonight and Wednesday. Wednesday night
through Friday active weather returns to the area with chances for
showers and thunderstorms. The best chances for rain appear to be
Wednesday night into Thursday morning associated with a warm front
and again on Friday associated with a cold frontal passage.
Temperatures will be near normal today and Wednesday with warm
readings expected on Thursday surging well into the 80s. A cool down
is expected into the weekend behind Friday/S cold front.


Short term...(today through thursday)
issued at 328 am EDT Tuesday Sep 2 2014

Rain chances are not none today with a cool front still progressing
south of the area. The front is located across Southern Lower
Michigan at 07z...but it should sag south of the area through the
course of the morning. Another caveat to keep an eye on is a
shortwave quickly moving our direction from Iowa. A few
showers/storms are associated with this wave as of 07z. Have
isolated/scattered wording in the forecast tapering off this
afternoon to dry/isolated as dew points drop in the wake of the
front. Dry weather is expected tonight and Wednesday with surface
high pressure in place across the Great Lakes.

Focus then shifts to a warm front surging our direction Wednesday
night. We will probably need to nudge chances for showers/storms up
Wednesday night into Thursday morning. Bumped chances up some
already...but they may need to go higher. Solid moisture advection
is noted at 850mb/S. The 850mb dew point advection seen in all the
models during this time frame usually equates to solid coverage of
showers/storms. All of the models show negative Li/S advecting into
the western County Warning Area...especially up towards Ludington Wednesday night.

Showers and storms remain possible into Thursday afternoon...but
feel we may be stabilized by morning convection some. Given
uncertainty though in convective evolution...have chances right
through the day. Clouds will be a significant factor in Thursday/S
high temperature forecast. At this point playing it in the middle to
upper 80s. We could push to around 90 though if better sunshine is

Long term...(thursday night through monday)
issued at 328 am EDT Tuesday Sep 2 2014

Seasonably warm weather will continue Thursday night and Friday.
A consensus of latest 00 medium range guidance suggests that a
strong cold front will bring potential for rain and thunderstorms
Thursday night through Friday.

High pressure will build in behind the front beginning Friday night
through the weekend resulting in partly cloudy to mostly clear skies
and much cooler temperatures. Maximum temperatures this weekend will only reach the
upper 60s to lower 70s with min temperatures mainly in the 40s to lower
50s. The ridge should remain in control of the weather pattern for next
Monday and bring fair weather with seasonable temperatures.


Aviation...(for the 06z tafs through 06z Tuesday night)
issued at 1145 PM EDT Monday Sep 1 2014

Primarily VFR conditions are anticipated overnight with isolated
lingering light rain showers. Patchy MVFR or IFR visbys/ceilings may
develop during the early morning hours Tuesday southeast of GRR.

There is also potential for some lower ceilings/visbys and a few showers
to clip mainly kjxn during the early to middle morning hours Tuesday.
However most of the showers should stay further south to southeast
of Southern Lower Michigan.

VFR conditions are anticipated Tuesday at all the terminals after
any patchy morning fog and low clouds mix out. Skies will clear with
VFR conditions continuing Tuesday night.


issued at 328 am EDT Tuesday Sep 2 2014

Fairly benign conditions are expected out on The Big Lake today into
Wednesday as high pressure settles into the area. Waves for the most
part today...tonight and Wednesday will be 2 feet or less.

Winds and waves look to ramp up Wednesday night into Thursday as
strong southerly winds develop. Thursday could be a beach
hazards/Small Craft Advisory day with the potential for Warm Beach
weather and large waves/dangerous currents. It would be another
south flow event where wind direction is critical. There is a big
difference in impacts from a 180 degree wind and a wind direction
from 210 degrees.


issued at 328 am EDT Tuesday Sep 2 2014

Labor Day/S rainfall has brought some within bank rises...but really
no concerns as the rises were all well within bank. Mainly dry
weather is expected today through Wednesday.

The next chances for significant rain will come Wednesday night into
Thursday morning along and ahead of a warm front...and again on
Friday ahead of a cold front. Both of these events could bring
locally heavy rains.


GRR watches/warnings/advisories...


short term...Duke
long term...Laurens

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