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Area forecast discussion 
National Weather Service Gaylord Michigan
1045 am EDT Tuesday Jul 28 2015

Update...
issued at 1044 am EDT Tuesday Jul 28 2015

Impact weather: none.

Synoptic pattern and observations:

Morning analysis...upper level ridging was directly overhead with
surface high pressure is situated over the eastern Great Lakes. A very
light southerly wind flow and sunny skies welcomed the morning with
warm temperatures in the 70s. Strong low pressure was at the
Montana/ND/srn Saskatchewan border while tighter middle level flow was
aligned from Wyoming through the Dakotas and Minnesota. One shortwave/mesoscale convective vortex
was crossing into the upper Mississippi Valley/arrowhead of Minnesota. This
wave was working in tandem with upper divergence and a decaying
low level jet...forcing showers and storms along/ahead of a cold front across
the far eastern Dakotas. These showers and storms were weakening due
to the decaying low level jet...and the fact that they are running into a
drier/more stable air mass.

Synoptic pattern evolution and associated weather:

Could see some high level cirrus increase through the morning from
the dying convection west of US...but the trend will be for this
cloud to erode out due to our dry air mass (see 12z apx morning
sounding). Skies will otherwise be sunny...especially as upper level
ridging increases through the day...bringing an impressive 588dm
height over northern Michigan. 800 mb temperatures rise a degree or two higher than
yesterday...and with deep mixing...highs will be in the 90-95f range
this afternoon. Relatively low dew points in the middle 50s to maybe
a shade above 60f will not make it feel too humid.

Am expecting to see inland cumulus development within low level
convergence regions from lake breezes this afternoon...but a lack of
sufficient low level moisture...and a little bit of a cap/warm layer
around 600mb will likely prohibit any showers/storms.

&&

Near term...(today through tonight)
issued at 343 am EDT Tuesday Jul 28 2015

High pressure remains locked over Michigan early this morning...
with clear skies and light/calm winds all around. After yet another
very warm day of temperatures well into the 80s to lower 90s...temperatures have
fallen into the 60s. The Hot Spot for the day was Pellston...soaring
to a sizzling 94 degrees.

High pressure...subsidence and dry air will remain centered over
Michigan for one more day...providing US with another mainly sunny
and very warm day. Weak synoptic low level flow will again lend to
lake breeze development this afternoon. A stray shower is not
completely out of the questions across interior sections of eastern Upper
Michigan again this afternoon as opposing lake breezes converge.
However...the chance is too small to include in the forecast given
dry air through the column combined with warm air aloft. Expect dry weather
through this evening with mainly clear skies and winds under 10 kts.

Weather finally begins to change late tonight as persistent high pressure
shifts east of Michigan as a cold front approaches from the west.
Clouds will begin to increase form west to east late tonight...and
so will chances of showers and storms for our far western County Warning Area. Latest
NAM is a bit slower to push precipitation into our western County Warning Area overnight...but
still cannot rule out at least a chance of showers and possible a
thunderstorm after 06z for locations west of a line from anj to pln
to cad. Instability will be rather unimpressive (500 joules or
less)...receiving no help from a diurnal instability prospective.
Certainly do not anticipate any chance for strong/severe storms...if
they happen at all. Will leave chance probability of precipitation in for the above outlined
areas...with only a slight chance for thunder.

Expect one more very warm day today as afternoon highs again warm
into the upper 80s to lower 90s...with overnight lows in the middle
60s to lower 70s.

&&

Short term...(wednesday through Thursday night)
issued at 343 am EDT Tuesday Jul 28 2015

(7/29)wednesday...models continue with the slow down the initial
timing of the front so that it is moving into west upper around 12z,
and exits NE lower by 00z. The middle-level moisture (700-500 mb layer
rh)continues to look thin with this front. Instability looks good in
the morning with the MLCAPES around 1000j/kg at 18z on the GFS
around apx. However, not really excited as we have seen this before
with the models showing lots of convection, only to have minimal
convection. As a retired forecaster once told ME, when you are in a
drought don't predict rain until it happens. So will keep the
thunder chances low with the chance of rain okay. Once past 00z, the
dry air moves in as well as the cold advection so the rain will be
out of the region. Am a little concerned that i'm optimistic with
the cloud cover Post frontal as the cold air at 850 mb could begin
to put US into some shallow unstable air over the lakes(they are
approaching 20c) and the 850 mb temperatures are around +10c in
Easter Lake Superior.

(7/30)thursday...despite the concern for cloud cover overnight on
Wednesday, it looks like the 850 mb temperatures rise during the day
and any clouds that were around overnight should begin to break up.
So will be mostly sunny with temperatures around normal as the sun
and the +15c 850 temperatures get US into the lower 80s around most
of north lower and upper 70s in east upper.

&&

Long term...(friday through monday)
issued at 343 am EDT Tuesday Jul 28 2015

Models are showing a slight difference in the upcoming weekend
and next week. The GFS continues the below normal temperatures and
a rather wet weekend as the 500 mb low sets up near James Bay. The
European model (ecmwf) is at or a little below normal with less rain, as a shallow
trough from the 500 mb low which is about 200 to 300 miles north
of the GFS position puts US in a slightly warmer, drier position.
Think that this may be the case, but will have to wait this out
until the models come to a better consensus.

&&

Aviation...(for the 12z tafs through 12z wednesday)
issued at 650 am EDT Tuesday Jul 28 2015

Conditions will remain VFR through Tuesday night at all northern lower
Michigan taf sites. High pressure will hold overhead through today
and will then slide east of Michigan tonight as a cold front
approaches from the west. Still appears that any chance of precipitation
with this front will hold off until late Tuesday night after
06z...and chances are too small through 12z to include in the taf for
now. Weak synoptic flow will again allow for lake breeze
development by afternoon.



&&

Marine...
issued at 343 am EDT Tuesday Jul 28 2015

Winds and waves will remain below Small Craft Advisory criteria through tonight as high
pressure remains centered over Michigan through today and then shifts
east of our state tonight. Dry weather will persist through this
evening...with mainly clear skies expected. Chances of showers and
storms will increase from west to east late tonight as a cold front
approaches. Winds and waves will approach Small Craft Advisory criteria on
Wednesday as southerly winds strengthen ahead of the cold front...
and then shift to the west in the wake of the front late Wednesday
afternoon and night.



&&

Apx watches/warnings/advisories...
Michigan...none.
LH...none.
Lm...none.
Ls...none.
&&

$$

Update...smd
near term...mlr
short term...jsl
long term...jsl
aviation...mlr
marine...mlr

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