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Area forecast discussion 
National Weather Service Grand Rapids Michigan
700 PM EDT Sat Apr 25 2015

Latest update...
aviation

Synopsis...
issued at 330 PM EDT Sat Apr 25 2015

Dry weather is expected for the next week as high pressure dominates
our weather. Temperatures will remain below normal Sunday and Monday
then gradually moderate. Above normal temperatures are expected next
weekend.

&&

Short term...(this evening through Monday night)
issued at 330 PM EDT Sat Apr 25 2015

The main issues in the short term are the frost potential at night
and the extent of daytime cloudiness.

Decided against issuing a frost advisory tonight since guidance
indicates winds holding up at 5 to 10 kts most of the night. This
should preclude a widespread frost however if/where winds do manage
to calm out late tonight some patchy frost is certainly possible.

Its a similar marginal scenario on Sunday night with guidance
showing the winds holding up... although perhaps a better chance of
the winds calming out on Monday night as the surface ridge axis gets
closer.

With shortwaves still swinging around the western side of the large
upper low to our east... will not get too optimistic with the cloud
cover forecast Sunday and Monday. In addition to any cloud cover
associated with the waves themselves... some diurnal enhancement is
also likely due to chilly 800 mb temperatures aloft of 0c to -3c. Cumulus
schemes are strongest east of Highway 131 so the Lakeshore counties
should see more sunshine than the inland areas.

In the near term... still a slight chance of some sprinkles or light
rain south of a Saugatuck to Battle Creek line for the next couple
hours otherwise expect clearing skies from north to south this
evening.

Long term...(tuesday through saturday)
issued at 330 PM EDT Sat Apr 25 2015

The long term portion will see mainly dry weather and increasing
temperatures that will reach 70 by the weekend.

Overall...the main storm track will be across the southern US which
is where most of the precipitation will be. Surface high pressure over the Great
Lakes will result in fairly dry low levels. However...the models
point toward a trough aloft moving across lower Michigan late
Tuesday. It/S possible we could see a sprinkle from this but more
likely we/ll be dry. Then ridging aloft will prolong the dryness
through Friday. A weak cold front approaches Saturday as the high to
the south moves east. South flow will develop on the back side of
the high and so the front will have a little more moisture to work
with.

&&

Aviation...(for the 00z tafs through 00z Sunday evening)
issued at 657 PM EDT Sat Apr 25 2015

VFR weather to prevail at taf sites as a drier airmass advects in
from northern lower Michigan.

&&

Marine...
issued at 330 PM EDT Sat Apr 25 2015

Increasing north winds on Sunday may necessitate small craft
advisories.



&&

Hydrology...
issued at 1157 am EDT Sat Apr 25 2015

River levels across southwest lower Michigan are steady or slowly
falling. Rain is possible across Southern Lower Michigan south of
Interstate 96 into tonight. Accumulations should be under a quarter
of an inch. Dry weather then returns through the week. Brief rises
are possible on the southern rivers... but river flooding is not
expected.

&&

GRR watches/warnings/advisories...
Michigan...none.
Lm...none.
&&

$$

Synopsis...Meade
short term...Meade
long term...99
aviation...mjs
hydrology...63
marine...Meade

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