Area forecast discussion
National Weather Service Gaylord Michigan
415 am EDT Thursday may 23 2013
Synopsis...
issued at 350 am EDT Thursday may 23 2013
Conditions will improve quickly from north to south today...as high
pressure works its way through the northern lakes. That high
pressure system will then influence our weather right on through the
Memorial Day weekend...giving plenty of sun but cool temperatures
each day...along with clear and chilly nights.
&&
Short term...(today through tonight)
issued at 350 am EDT Thursday may 23 2013
Currently...an upper level low pressure drifting across Wisconsin
is getting absorbed into a greater longwave troughing carving
southward out of Ontario. This is allowing fgen to weaken across
far Northern Lake Michigan/straits/Drummond Island. Regardless...the
steady precipitation continues to fall in most areas of northern
Michigan...especially across the remaining fgen/deformation. In
the meantime...surface low pressure and low level troughing continues
a slow drift eastward from near the Saginaw Bay region. A stronger
push of cold air is currently blasting southward through the
region as well...and the drier low level air and gusty winds up to
roughly 25 knots...were eating away at the lowest of clouds and
reduced visibilities/any fog. Temperatures were falling into the
40s. So...wet of cold.
Today...a gradual west to east movement of the precipitation and
clouds can be anticipated...as the upper level troughing will
sweep across northern Michigan. While the overall fgen forcing will
continue to wane...deep moisture and deformation will continue to
produce light rain. Should start to see increasing rainfall
coverage across NE lower. Not only does the whole pattern shift
this way...but shortwave energy wrapping up across this area from
Wisconsin should squeeze out more rainfall behind the departing
low level troughing. Inherited grids looked really good on timing
the precipitation out of here...leaving all of eastern upper by
middle morning...northwest lower around middle day...and finally NE lower
during the afternoon. Strong high pressure and a Near Wall of very
dry air then settle into the region. Skies will go rather quickly
from cloudy to sunny. High temperatures will be in the 50s. Winds will be
rather gusty maxing out at up to 25-30mph.
Tonight...the high pressure will be in total control as it
continues to filter through the western Great Lakes. Maybe some
shreds of cirrus...but skies will be clear. With temperatures
starting in the 50s...and cold advection continuing...its shaping
up to be a cold night. Issues surrounding tonight...revolve around
the potential for frost. While the clear skies and dry air are
definitely in play...the winds are the trickier part. Winds will
still be gusting into the evening...before gradually winding down
overnight. While many low lying areas will decouple...some of the
more exposed areas will still feel a touch of wind...as the bl
winds are still going at 10kt west...to as much as 20kts east
through 12z. This could keep temperatures from falling as far as models
suggest. Do see temperatures falling into the middle 30s...with some lower
30s...especially west. A frost advisory has been hoisted for all
but the far NE lower counties...but tomorrow night is looking to
be the better candidate for widespread frost with the high
pressure directly overhead...and more relaxed bl winds.
&&
Long term...(friday through wednesday)
issued at 350 am EDT Thursday may 23 2013
Friday...high pressure continue over the region and keeps the
forecast area dry. The 850 mb temperatures begin to recover some
during the day reaching +2c over most of the forecast area by 00z.
Looking at the model soundings both the GFS and the European model (ecmwf) mix around
850 mb. So have temperatures rising to either side of 60 with full
sun and mixing to 850 mb would yield those temperatures.
Friday night...looks like another possible frost night. Both the GFS
and ecwmf are suggesting that there could be some cloud cover, but
that it GOES away by 12z. The 850 mb temperatures are a little
warmer than they were on Thursday night, so think that frost has a
little less areal coverage than Thursday. The coolest temperatures
will be in NE lower and portions of east upper where the 850 mb
temperatures are closer to 0c.
Saturday...the high pressure remains in place and continues to keep
the place dry. The 850 mb temperatures begin to rise a few degrees
(to around +4c) and with the sunshine, would expect that the high
temperatures will be in the lower to middle 60s. Overnight, the 850 mb
temperatures drop a little back to +2c around 12z, so with an
inversion, the low temperatures will be between upper 30s to around
40. So no frost expected as we get into the weekend.
Extended (sunday through wednesday)...Sunday, high pressure
continues, so the weekend itself looks good for getting outside.
Monday, north Michigan looks dry. Models are still holding firm for
mostly sunny. Overnight, the clouds begin to increase. The GFS is
trying to bring rain into the forecast area. Think this is too fast
and based on the quantitative precipitation forecast "bomb" and surface low development, think this is
due to convective feedback. So will leave the night dry. Tuesday,
the clouds keep increasing and with the south wind, the lower 70s
would be expected for the day. There could be some thunder overnight
in east upper as the 500 mb ridge flattens from a vorticity Max, and becomes
the leading edge of thunderstorms. Wednesday, looks like with the
south flow over the Flat Ridge at 500 mb there could be some
thunderstorms with the middle level (700-500 mb) lapse rates around
7c/km. So will continue with the chances. The European model (ecmwf) and the GFS both
have some sort of high quantitative precipitation forecast value over some portion of the forecast
area, so there could be some sort of mesoscale convective system overnight with a 30 knot
low level jet possible. We'll see.
&&
Aviation...(for the 06z tafs through 06z Thursday night)
issued at 1156 PM EDT Wednesday may 22 2013
Periods of rain will continue at all terminal sites the remainder
of the night...as will periodic IFR conditions. However...ceilings
and visibilities will show a rather rapid improvement from north
to south as northerly winds intensify after 08z and help drag
drier air into the area...lifting ceilings up toward MVFR or even
low end VFR. That trend will continue through midday or early
afternoon as skies clear completely while winds get a little gusty
up to 20-25 knots for a time. Things will calm down into the
evening as high pressure arrives...with clear skies and winds
dropping to 10 knots or less.
&&
Marine...
issued at 350 am EDT Thursday may 23 2013
A strong cold front is diving southward through the Great Lakes
and winds have been increasing to gusts securely in the advisory
levels. As colder air flows in through the day...the instability
will deepen and solid 25-30kt gusts are expected to develop over
all areas. High pressure does sneak into the western Great Lakes
tonight...before moving overhead and holding firm through Memorial
Day weekend. A Small Craft Advisory will continue for the
day...with Lake Huron nearshores maybe needing headlines extended
into the evening.
&&
Apx watches/warnings/advisories...
Michigan...frost advisory from 2 am to 8 am EDT Friday for miz016-017-
019>023-025>029-031>034.
LH...Small Craft Advisory until 8 PM EDT this evening for lhz345>349.
Lm...Small Craft Advisory until 8 PM EDT this evening for lmz323-341-
342-344>346.
Ls...Small Craft Advisory until 8 PM EDT this evening for lsz321-322.
&&
$$
Synopsis...jl
short term...South Dakota
long term...jl
aviation...Lawrence
marine...South Dakota
