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Area forecast discussion 
National Weather Service Grand Rapids Michigan
740 am EDT sun Aug 30 2015

Latest update...

issued at 247 am EDT sun Aug 30 2015

Rain showers will gradually taper off this morning and areas of
fog will dissipate by noon. Fair and warmer weather is expected
for much of the week.


Short term...(today through tuesday)
issued at 247 am EDT sun Aug 30 2015

Forecast issues in the near term include timing of the showers
ending today and chance for isolated showers or thunderstorms
across the southern forecast area on Tuesday.

Will continue a slight chance for showers across the southeast
zones this morning. Expect showers to end by afternoon and low
clouds and fog to gradually decrease by afternoon as the upper
trough axis moves east and heights rise.

Even as upper ridging builds in...there will be sufficient low
level moisture for some diurnal showers or thunderstorms across
the Ohio Valley on Monday and this is expected to advect north on
Tuesday as flow GOES more southerly.

We will have slight chance probability of precipitation across the southern tier to
account for this and this may have to be expanded with time as
both the GFS and European model (ecmwf) have consistently shown diurnal enhancement
of quantitative precipitation forecast suggesting at least isolated showers and storms on Tuesday.

Long term...(tuesday night through saturday)
issued at 247 am EDT sun Aug 30 2015

Temperatures will average above to much above normal through the
long range forecast period with a persistent upper level ridge over
the eastern Continental U.S. Through the long range forecast period. Maximum temperatures
will reach the middle 80s to near 90 degrees daily with min temperatures
mainly in the 60s. It will be rather humid through the long term
forecast period as well with dew points in the 60s.

We cannot rule out potential for an isolated shower or thunderstorm
daily middle to late week mainly during the afternoon and early evening
hours when instability will be maximized. However it appears that
most days will lack a forcing mechanism for convective initiation to
occur with the exception of a potential lake breeze and resulting
lake breeze convergence daily. However the vast majority of the long
range forecast period should be very warm to hot and dry.


Aviation...(for the 12z tafs through 12z Monday morning)
issued at 738 am EDT sun Aug 30 2015

Fog and low clouds will bring IFR and patchy LIFR conditions this
morning with conditions improving to MVFR by 16z and then VFR by
18z. Winds will continue to be below 10 knots through tonight with
fog forming again by 06z and more IFR and LIFR by 12z Monday.


issued at 247 am EDT sun Aug 30 2015

Winds and waves will remain relatively light the next few days.
Areas of fog will continue though this morning.


issued at 139 PM EDT Sat Aug 29 2015

Most locations saw less than a half inch of rain last night into
today. This should not cause Hydro concerns. Much of next week
looks largely dry.


GRR watches/warnings/advisories...


short term...ostuno
long term...Laurens
hydrology...63/jk marine...jk

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