Area forecast discussion
National Weather Service Grand Rapids Michigan
704 am EDT Thursday Jun 20 2013
Latest update...
aviation
Synopsis...
issued at 330 am EDT Thursday Jun 20 2013
High pressure will continue to bring fair weather through Friday and
it will be warm. Increasingly hot and humid weather is anticipated
this weekend into next week with a chance of thunderstorms beginning
Friday night through the weekend into early next week.
&&
Short term...(today through Saturday afternoon)
issued at 330 am EDT Thursday Jun 20 2013
The primary short term forecast challenge is to determine probabilities
for thunderstorms Friday night through Saturday.
High pressure will continue in control of the weather pattern today
through Friday bringing fair and warm weather. Maximum temperatures today will reach
the upper 70s to lower 80s and maximum temperatures Friday will reach the middle
to upper 80s in a continued southerly flow warm air advection regime.
Scattered showers and thunderstorms are possible late Friday night and
Saturday as heat and humidity continue to build and dew points climb
through the 60s. A potential triggering mechanism for convective
development will be the warm front over our northern forecast area as
well as a couple of shortwaves which will move through.
800 mb Li/S should fall to around -1 to -3 late Friday night through
Saturday and there is potential for sb convective available potential energy to reach 2-3k j/kg
Saturday afternoon. So scattered showers and storms are expected
Friday night through Saturday though most of the time dry conditions
should prevail.
Long term...(saturday through wednesday)
issued at 330 am EDT Thursday Jun 20 2013
Forecast issue in the extended is how extensive showers and
thunderstorms will be each day as warm humid southwest flow
dominates with flat upper ridging. Looks like the best chances of
rain will be late in the period as the upper ridge begins to break
down. There are signs of an mesoscale convective system forming Tuesday across the upper
plains then riding the top of the ridge into the northern forecast
area late in the day or Tuesday night. The outflow boundaries then
could focus convection across the southern forecast area on
Wednesday.
&&
Aviation...(for the 12z tafs through 12z Friday morning)
issued at 704 am EDT Thursday Jun 20 2013
VFR conditions through tonight with south to southwest winds below
10 knots.
&&
Marine...
issued at 330 am EDT Thursday Jun 20 2013
Light winds and minimal waves are expected through Friday. There is
a chance of thunderstorms Friday night through the weekend with
potential hazards to boaters and swimmers from any thunderstorms
that develop.
&&
Hydrology...
issued at 330 am EDT Thursday Jun 20 2013
No precipitation expected through Friday. Scattered thunderstorms
are possible Friday night through the weekend into early next week
but at this time no hydrology issues are expected to occur in the
next week.
&&
GRR watches/warnings/advisories...
Michigan...none.
Lm...none.
&&
$$
Synopsis...Laurens
short term...Laurens
long term...ostuno
aviation...ostuno
hydrology...Laurens
marine...Laurens
