Area forecast discussion
National Weather Service Grand Rapids Michigan
739 am EDT Thursday may 23 2013
Latest update...
aviation
Synopsis...
issued at 327 am EDT Thursday may 23 2013
Showers will linger through the morning hours...but then as drier
air moves in from the northwest the rains will come to an end
through the afternoon and early evening from northwest to
southeast. After a gloomy start to the day most areas will see
some sunshine by late afternoon or early evening. This clearing
will be the start of quiet period of weather which should last
throughout the Holiday weekend.
It will be much cooler today with highs only 55 to 60. Patchy frost
will be seen tonight north of I-96. However temperatures will
gradually rebound into the 60s for Friday and Saturday...and mainly
into the 70s for Sunday through Wednesday. The next chance of rain
should hold off until Tuesday and Tuesday night.
&&
Update...
issued at 552 am EDT Thursday may 23 2013
I added scattered thunderstorms to the grids for the next few
hours as we are getting some lighting strikes over western
Montcalm and northern Kent County (545 am) with the showers there.
The mu cape is near zero so I do not see this turning out to be
much but since there is lighting now... seems reasonable to add it
to the forecast for the next few hours.
&&
Short term...(today through saturday)
issued at 327 am EDT Thursday may 23 2013
A cold front cut across the County Warning Area this morning and it will continue to
sag to the south today. Fgen behind the front was supporting a band
of showers over eastern WI/Lake Michigan early this. This rain will swing
through the County Warning Area from northwest to southeast through the course of the day. Upper
dynamics were also helping this area of rain...and the right
entrance
region of the jet will slide over the County Warning Area with the rain. So
needless to say the band of rain should hold together and it looks
wet through the morning. Then the back edge of the rain will
gradually sag southeast through the County Warning Area through the afternoon and early
evening. Much drier air moves in and skies will clear late today.
This should give most areas a late afternoon/early evening high temperature
as a bit of sunshine boosts the temperatures up a bit.
Will go ahead with a frost advisory across the northern County Warning Area
tonight. This does not look like a prolong event with the nights
being so short this time of year. Also with the winds likely
staying up through the evening the actually time frost will develop
should only be 3 to 5 hours. Localized areas may fall to below
freezing in the normally cold low spots...but this should be too
brief and too isolated to need to consider a freeze warning.
High pressure and quiet weather prevails for Friday and Saturday.
Frost potential appear to be lower for Friday night given that some
middle/hi clouds should be moving in on the heels of warm advection
aloft. Will mention patchy frost for now and will need to monitor
cloud trends. Daytime temperatures warming slightly each day.
Long term...(saturday night through wednesday)
issued at 327 am EDT Thursday may 23 2013
A classic Hudson Bay high will visit our area into Monday providing
little in the way of cloud cover and slightly below normal
temperatures through Memorial Day. This will block any attempts of
southern stream shortwaves from bringing any clouds and
precipitation into the area.
Beyond Memorial Day the forecast gets more uncertain. While we start
out with an Omega block type pattern (which is why it should stay
mostly clear into Memorial day) over time a powerful storm currently
near Japan crosses the North Pacific gaining support from a system
in the Bering Sea late in this weekend. The system reaches the West
Coast in the Wednesday time frame. Now there already a system
stalled along the West Coast. When the Japan system gets west of the
dateline... that will force the current system inland and that will
try to flatten the large ridge (1-2 Standard deviations from normal
on the 500 mb heights) by midweek. That then sets US up to be in the
line of fire for shortwaves traveling east on the southern stream
jet. So just how this plays out is anyone guess... since the
primary player in all of this has to cross the Pacific Ocean yet.
So... all that being so I have to admit there will be a chance of
showers and thunderstorms from Tuesday afternoon on. Thus in
increased the pop to around 30 percent from then on through the rest of
the forecast. What this means is the front stalls near US. Another
aspect to this is it should get warm to hot as the upper ridge is
pushed east a touch middle to late week. I could see highs well up
into the 80s from Wednesday on. Again... timing shortwaves and such
will be an issue with the temperatures... but bottom line Summer
like weather returns by Wednesday continues well beyond Wednesday.
&&
Aviation...(for the 12z tafs through 12z Friday morning)
issued at 738 am EDT Thursday may 23 2013
IFR ceilings/visibility are expected at all taf sites through the rest of
the morning as rain... heavy at times spreads through the area
just behind the cold front. Jxn...which is still VFR will become
IFR by 13z-14z.
The rain should end from northwest to southeast during the early
afternoon then a slow clearing will follow. By 00z or so I expect
skies to be nearly clear at all taf sites. Overnight expect clear
skies and north winds under 10 knots.
&&
Marine...
issued at 327 am EDT Thursday may 23 2013
North winds flowing down the length of the lake will produce
increasingly rough conditions on the lake today. Highest waves
early this morning will be north of Whitehall...but these rougher
conditions will traverse south and include all of the nearshore
areas by late morning. Waves may build as high as 10 feet off of St
Joseph by this evening. Winds and waves will slowly diminish
tonight into early Friday as high pressure moves in.
&&
Fire weather...
issued at 327 am EDT Thursday may 23 2013
More rain today will keep fire danger low. Much drier air arrives
for Friday and Saturday with daytime relative humidity values lowering to around 35
percent. However winds will remain under 10 miles per hour for much of Friday
and Saturday.
&&
Hydrology...
issued at 327 am EDT Thursday may 23 2013
Additional rain today will be persistent...but will be on the light
side. Generally less than a quarter of inch is expected. River
levels are high with one advisory valid for the Muskegon river near
Croton. River levels should begin to slowly fall late today as the
beginning of a dry spell moves in.
&&
GRR watches/warnings/advisories...
Michigan...frost advisory from 1 am to 7 am EDT Friday for miz037>040-
044>046.
Lm...Small Craft Advisory until 4 am EDT Friday for lmz847>849.
Small Craft Advisory until noon EDT Friday for lmz844>846.
&&
$$
Update...wdm
synopsis...jk
short term...jk
long term...wdm
aviation...wdm
fire weather...jk
hydrology...jk
marine...jk
