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Area forecast discussion 
National Weather Service Gaylord Michigan
348 am EDT Monday Jul 6 2015

Near term...(today through tonight)
issued at 348 am EDT Monday Jul 6 2015

High impact weather potential...turning breezy this afternoon with
somewhat enhanced fire danger...and beach hazards along Lake Michigan.
T-storms tonight with heavy rain but minimal severe.

Upstream cold front extends from far northern near Isle
Royale...just east of Duluth...and on to a surface wave in far northwest
Iowa. Considerable deep convection was occurring along and
immediately behind this front...though organization/intensity has
been waning overnight. The cold front will enter eastern upper
toward midnight...and will be pushing through NE lower by 12z/8am. At
this moment...skies are almost clear in northern Michigan...eastern
upper/northwest lower Michigan starting to see some cirrus blowoff from the
upstream weather. Precipitation trends are the main concern...temps/winds
today are also of note.

Today...present airmass is extremely dry above the inversion...per
00z apx/grb soundings. That air aloft is also quite warm (700mb
temperatures 9c at both sites). Model-prognosticated cins today are around 100
j/kg. Thus...even as we slowly get warmer/more humid...we are capped
off to deep convection until stronger forcing arrives. There/S a
chance for some decaying -shra to reach western chip/Mack counties
toward early evening...along with perhaps northwest lower Michigan west of tvc. But
Don/T anticipate any thunder before 00z.

Ongoing clouds will thin as move east toward northern Michigan. Expect
the more substantial increase in cloud cover to wait until this
afternoon. Until then...the smoke layer aloft is the primary
obstacle to getting nice and toasty. But we eventually warmed up
quite nicely yesterday...and we should manage to reach guidance
maximum temperatures today. That puts highs mainly in the low/middle 80s...with
some upper 80s at tvc/apn and other downsloping locales.

Models have a little baggier with the pressure gradient in the warm
sector in our neck of the Woods. Some late afternoon 30-35mph gusts
appear likely to arrive in western chip/Mack counties...but we/ll
see less than that elsewhere...and in most places much less.
Still...increasing wind/wave action on Lake Michigan in particular will
result in potentially dangerous swim conditions. (And for once...
this is happening on a day where people might actually want to go
to the beach.)

There is also a somewhat elevated fire risk...after several days
of dry weather...and warm temperatures and increasing winds today.

Tonight...cold front will slowly work into and across northern
Michigan...and the precipitation threat will slowly accompany it. Shortwaves
moving across the upper MS valley and digging toward western
Superior will lower heights...and provide the forcing aloft to erode
and eventually overcome the cap. Primary instability plume will
build into central/Southern Lower Michigan overnight. Of course...the planetary boundary layer
will be stabilizing by then. The loss of surface cold pool as a
forcing mechanism for new updrafts will lead to a lack of
organization...much like is being seen upstream early this
morning. Best chance for thunder is near/south of a tvc-apn line
overnight...where MUCAPES might near 1500j/kg. But 0-6km bulk
shear values are only 20-25kt in the warm sector...and again the
planetary boundary layer will be stable. So difficult to see too much of a severe threat.
However...there will be a narrow axis of precipitable waters nearing 2 some healthy rainfall rates can be anticipated.
Localized 1-2 inch amounts can be expected in northwest lower and eastern
Upper Michigan by morning...would not rule out something more than

As for timing...most of the convection will be after 11pm. Will
gradually expand categorical probability of precipitation in eastern upper...northwest and north
central lower Michigan after that. Meanwhile...only a small chance of rain showers
by 12z in the far southeast (osc/Tawas/standish).

Min temperatures will range widely...from the middle 50s in western
chip/ near 70f along the Saginaw Bay coast.


Short term...(tuesday through Wednesday night)
issued at 348 am EDT Monday Jul 6 2015

The surface cold front continues to clear the forecast area Tuesday
morning. High pressure then builds back into the region later
Tuesday and should hold through much if not all of the remainder of
the work week. Return flow in combination with a possible short wave
will bring more chances for showers and thunderstorms to the region
next weekend. The main short term forecast concerns are centered
around the timing of exiting probability of precipitation Tuesday.

Tuesday...there are model differences as to how quickly the
front/precipitation and subsequent clearing occurs. Will lean toward
the slightly faster solutions...though probability of precipitation are expected to linger
through the morning hours across much of northern lower...especially
across southeast zones where low chance probability of precipitation will linger into early
afternoon as well. It will be breezy...cooler and less humid as well
with highs in the middle 60s to lower 70s.

Tuesday night through Wednesday night...high pressure builds in
leading to mostly clear skies along with diminishing winds and much
cooler nighttime temperatures. Lows in the middle 40s to the lower
50s. Highs Wednesday in the lower and middle 70s.


Long term...(thursday through sunday)
issued at 348 am EDT Monday Jul 6 2015

Extended models continue to struggle with the finer details of the
evolution of the pattern...though they are gravitating toward a
common solution. The main issue is how far north moisture from low
pressure passing by to our south will be able to make it. The GFS
which is now gathering some support from the NAM continues to be the
farthest north. Meanwhile...the more consistent European model (ecmwf) keeps this
system off to our south...not really threatening the forecast area
with any precipitation. So will continue with the dry forecast
through Friday...betting on the surface high holding strong while
keeping in mind this could change. Return flow in combination with a
possible pair of short waves will increase probability of precipitation over the
weekend...but this does not appear to be a sure bet either at this
point. The slow warming trend through the end of the work week into
the weekend still looks on track with temperatures approaching
seasonal averages by Saturday which should continue into Sunday as


Aviation...(for the 06z tafs through 06z Monday night)
issued at 138 am EDT Monday Jul 6 2015

MVFR to at times IFR fog pln overnight. MVFR conditions in rain showers
pln/tvc/mbl toward midnight Monday night.

A touch of fog will be seen overnight in pln...with MVFR to IFR
conditions. A cold front will move into northern Michigan late tonight.
Rain showers/embedded thunderstorms and rain will move through with the front. This will just
be getting underway at the tail end of this taf period...with MVFR
conditions at pln/tvc/mbl.

S to SW winds Monday...a bit gusty in the afternoon.


issued at 348 am EDT Monday Jul 6 2015

Still assessing need for additional small craft headlines
today/tonight. In general though...SW flow ahead of a cold front
that arrives tonight looks a little less impressive than it did
earlier. Do anticipate adding Whitefish Bay/St Marys River to
ongoing marine headlines. T-storms tonight will bring heavy rain
and brief gusty winds...would not rule out needing to issue
specialmarine warnings tonight (especially after 10 pm).


Apx watches/warnings/advisories...
Michigan...Beach hazards statement from 11 am EDT this morning through late
tonight for miz015-020-025-031.

Lm...Small Craft Advisory from 11 am this morning to 6 am EDT Tuesday
for lmz341-345-346.



Near term...jaz
short term...Sullivan
long term...Sullivan

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