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Area forecast discussion 
National Weather Service Grand Rapids Michigan
735 am EDT Friday Oct 24 2014

Latest update...

issued at 330 am EDT Friday Oct 24 2014

Fairly benign weather will continue through the weekend with dry
weather currently forecast through Sunday. A cold front will sweep
through the region Saturday morning...but it should pass through
dry. High temperatures Friday through Sunday will be slightly above
normal topping out around 60 degrees each day. Normal highs for this
time of year are in the middle to upper 50s. A low pressure system
moving through the Great Lakes early next week will bring chances
for showers and thunderstorms along with warm air. Highs Monday and
Tuesday will push towards 70 degrees...especially across Southern
Lower Michigan.


Short term...(today through sunday)
issued at 330 am EDT Friday Oct 24 2014

No real concerns in the short term with dry weather forecast through
the period. The main issue will be clouds.

Widespread stratus and stratocumulus located upstream will move into
lower Michigan today and should provide a mostly cloudy day. There
is some indication that the clouds may be trying to exit the eastern
County Warning Area late in the day with clearing in the west...but thinking we will
likely hang on to clouds much of the day.

Clearing will occur tonight for a time...before moisture streams
back in ahead of the cold front approaching from the west.
general a partly cloudy night...but we should turn mostly cloudy in
most areas by daybreak Saturday.

The front on Saturday still looks to traverse the area dry. Moisture
is not all that impressive in the 1000-700mb layer and most of the
dynamics remain to the north. The associated upper wave is located
in the northern Great Lakes with little if any vertical motion down
our way. Clouds should be the main impact with this system.

The clouds will exit the east Saturday afternoon...with clearing
taking place from west to east through the day. High pressure
settles into the area for Saturday night and Sunday with mostly
clear skies.

Long term...(sunday night through thursday)
issued at 330 am EDT Friday Oct 24 2014

The models have trended into very good agreement through much of the
long term period. Much warmer air arrives at the beginning of the
long term as a long wave upper trough develops over The Rockies.
This pumps the warmer and more moist air into the region. A warm
front should come through Monday morning. All the models show some
convection north of the front late Sunday night into Monday along
and north of I-96. I increased probability of precipitation slightly over the northern County Warning Area
with this front. By Monday afternoon 800 mb temperatures surge to +14c which
should support maximum temperatures of 65 to 70 across much of the County Warning Area...
possibly higher...dependent on if any sun comes through behind the

The models have trended quicker with a cold front that appears to
come through Tuesday morning now. We should see a line of showers
and a few thunderstorms with it. Then...if the timing verifies we
should see falling temperatures Tuesday afternoon as 800 mb temperatures crash. In
fact the models have also trended colder behind this front with 800 mb
temperatures plunging to around -1c by Tuesday night. Have low probability of precipitation for
Tuesday night...but if the colder trend continues we may need to
increase probability of precipitation as some lake effect showers could be possible then.

The middle week period looks mainly dry and seasonably cool as the long
wave upper trough exits and zonal flow develops.


Aviation...(for the 12z tafs through 12z Saturday morning)
issued at 735 am EDT Friday Oct 24 2014

Main aviation concern the next 24 hours is MVFR
conditions...mainly from ceilings today and again late tonight.
Poor aviation conditions are currently located upstream across
Wisconsin and they will try to move into the lower peninsula
today. Not expecting IFR at this point...but MVFR conditions are
likely for kazo...kgrr and kmkg. To the klan and kjxn
not thinking the lower ceilings will make it that far east and
kept them VFR. The clouds should scatter out from west to east
this evening...from 20z to 00z. Mainly clear skies are expected
for a time after 00z...with MVFR ceilings spreading back in late
tonight...after 09z or so. Winds will generally be southwest at 5
to 10 knots.


issued at 330 am EDT Friday Oct 24 2014

Light southerly flow today will keep wave heights in check. South
winds begin to increase tonight ahead of a cold front but should
stay just below Small Craft Advisory criteria. The next time frame
of concern will be Saturday behind a cold front where west and
northwest winds will likely ramp into the 15 to 25 knot range. Waves
should build into the 3 to 6 foot range. At this point will hold off
on a period 3 Small Craft Advisory. One will likely be need though.


issued at 330 am EDT Friday Oct 24 2014

Hydro concerns are limited through this weekend with low river
levels and no precipitation forecast. The next chance for solid rain
comes Sunday night into early next week as a low pressure system
traverses the area. Precipitable water values increase to around 1.25 inches which
is above the 75 percentile for this time of year. The amount of rain
expected though should be able to be absorbed without issue given
low flows.


GRR watches/warnings/advisories...


short term...Duke
long term...jk

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