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Area forecast discussion 
National Weather Service Grand Rapids Michigan
330 am EDT sun Apr 26 2015

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

issued at 330 am EDT sun Apr 26 2015

High pressure will remain in control of the weather pattern
through the upccoming week and bring predominantly dry and fair
weather. Temperatures will undergo a gradual moderating trend
through the week with above normal temperatures expected by next


Short term...(today through tuesday)
issued at 330 am EDT sun Apr 26 2015

Short term forecast concerns are fairly minimal with a surface ridge in
control of the weather pattern through the short term forecast period. An
upper level disturbance dropping down from the north may produce
isolated to scattered diurnally driven showers by middle to late afternoon
into this evening over eastern lower Michigan.

However a consensus of 00z short range guidance suggests that dry
weather should continue today with this dry airmass in place. A fair
amount of cloud cover should develop late this morning and
afternoon and some of that will linger tonight with min temperatures
tonight in the 30s. Frost potential tonight seems low overall
given partial cloud cover and some light but persistent boundary
layer mixing overnight.

A surface high pressure ridge will bring fair weather Monday through
Tuesday with seasonably cool temperatures. Any scattered light rain
showers tonight into Monday driven by upper level disturbance
swinging in from the north around the western periphery of the
upper trough axis should stay east of our forecast area.

Long term...(tuesday night through saturday)
issued at 330 am EDT sun Apr 26 2015

There are still some differences in the long term models regarding
the details of the evolution of the upper pattern. Overall
though...the main messages are mainly dry conditions with a
moderating trend. High temperatures should nudge upward a bit each
day with 60s expected the latter half of the work week with 70s a
decent bet next weekend.

Two time frames of concern in regard to the potential for light rain
showers...the first being Wednesday afternoon through Thursday
evening. The second being next weekend.

Wednesday afternoon through Thursday evening an upper trough will be
pivoting southeast through the Great Lakes. The GFS and ecwmf are
kicking out light precipitation while the Canadian Gem is keeping
things dry. Given a dry surface pattern (high pressure in place) and
the lack of deep moisture will roll with a dry forecast.

Next weekend...a shortwave at 500mb/S and a weak surface trough are
forecast to move through the area. Not overly excited about the
chances for light rain next weekend either...but have some probability of precipitation in
the forecast for Friday night and Saturday...20-30 percent. Low
confidence forecast regarding chances for rain next weekend.


Aviation...(for the 06z tafs through 06z Sunday night)
issued at 1108 PM EDT Sat Apr 25 2015

VFR weather to prevail through Sunday. I did reflect gusts in the
forecast Sunday...especially for kmkg...kazo...kbtl and kgrr. Lake
breeze could move inland resulting in a wind shift and gusts over
20 knots.


issued at 330 am EDT sun Apr 26 2015

Northerly winds will increase somewhat this afternoon and again
Monday afternoon and result in increasing wave heights mainly
over our southern nearshore zones. Wave heights may very briefly
flirt with small craft criteria south of Holland late this afternoon
and early evening but should not exceed 2 to 4 feet the next couple
of days.


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


GRR watches/warnings/advisories...


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

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