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Area forecast discussion 
National Weather Service Duluth Minnesota
issued by National Weather Service Twin Cities/Chanhassen Minnesota
1257 PM CDT Thursday Jul 24 2014

Synopsis...
issued at 310 am CDT Thursday Jul 24 2014

Surface high is positioned over the County Warning Area early this morning with mostly
clear skies and calm conditions. Temperatures have lowered to the low to
middle 40s from The Arrowhead into northwestern Wisconsin. Patchy fog is
developing across the region and should see some increase in areal
coverage until 11z.

&&

Short term...(today and tomorrow)
issued at 310 am CDT Thursday Jul 24 2014

Today...surface high shifts southeast of the region allowing some
increase in the warm advection pattern. 850 mb moisture transport magnitude
has trended downward from yesterdays model output. Multi model quantitative precipitation forecast is
much slower in advancing measurable into the region. Have opted to
remove probability of precipitation from todays forecast with collaboration from surrounding
offices. Maximum temperatures a degree or two higher based on forecast 925 temperatures. Scattered
clouds likely around 5kft based on latest BUFKIT moisture profiles.

Tonight...surface low will make its way across sodak with development of
a low level jet expected to occur from eastern Nebraska to southwestern Minnesota by midnight and then
stretch from Kansas to northern Iowa by 12z. It appears a mesoscale convective system/mesoscale convective complex will
develop across the plains and track into southern Minnesota/northern Iowa by early
morning on the northern fringe of a middle level cap. An inverted surface trough
from eastern sodak to southern Manitoba may promote increased boundary layer
convergence however middle level warming may provide enough inhibition to
restrict convective potential. Have lowered probability of precipitation and slowed arrival
into arrowhead. It is possible that the level of middle level warming may
negate probability of precipitation entirely across a larger part of the County Warning Area and updates may
be required.

Tomorrow...middle level ridge will flatten as the surface frontal boundary slowly
moves towards the Northland. Overall thermodynamics suggest that
increasing boundary layer instability will develop as the middle/upper cloud
layer advects east by midday. Frontal convergence doesnt materialize
until late afternoon over western edge of County Warning Area. With little boundary layer
convergence to focus initiation and a relatively warm middle layer
still in existence...convection may have some difficulty organizing.
At this time highest probability of development may be across northwestern County Warning Area in
an area of greatest surface based instability/lower cin and 35/45kt deep
layer shear. Maximum temperatures will be a little tricky as warm advection
lifts low level thicknesses however cloud cover will mitigate some of
that warming in eastern County Warning Area.

Long term...(friday night through wednesday)
issued at 310 am CDT Thursday Jul 24 2014

The upper level flow will transition from zonal with an upper low
over southeast sk early in the period...to northerly flow by early
next week.

The upper low over sk will move through the Northland this weekend
bringing a chance for showers and thunderstorms through Sunday.
Precipitation coverage will be at a minimum Friday night as forcing
weakens. The upper low will then continue southeast Saturday into
Sunday bringing a better chance for rain into the region. The European model (ecmwf)
is slower with the upper low...and is likely more accurate and has
support from the NAM/Gem. Saturday night will feature the highest
probability of precipitation as the upper wave moves through the Northland. Highs Saturday
will reach the upper seventies to middle eighties.

We increased temperatures a bit Sunday due to the expected slower arrival
of the upper wave and cooler temperatures. Monday should be dry with the
Northland sandwiched between the surface high over the northern
plains and low pressure well off to the east. Highs Monday will
range from 70-75.

The upper low will get absorbed into the larger low centered near
James Bay Monday. The upper low will then retrograde some. We have
some low probability of precipitation Tuesday/Wednesday as a weak wave or two will move
through in the northerly flow aloft. Highs will be mainly in the middle
to upper seventies.

&&

Aviation...(for the 18z tafs through 18z Friday afternoon)
issued at CDT Thursday Jul 24 2014

Confidence is increasing that an area of scattered thunderstorms
will drop south across northern and central Minnesota
tonight...but the details still need to be worked out. The storms
this afternoon will miss the taf sites to the southwest...kbrd is
really the only site that might get grazed by a few showers. The
second batch tonight should form a little farther north and
east...which would put it on a better track toward the taf sites
in northern Minnesota and eventually into northwest WI. We aren't totally
clear on the specific timing /or location/...but the best window
looks like 06-12z. We kept the thunder out of kinl with the 18z
issuance...but it's close and we will look to update at 21z. We
might need to include thunder in the taf when we update. A lot of
the forecasting models we look at are calling for MVFR/IFR
stratus late tonight...but this is highly dependent on how much
rain falls. This really isn't a climatologically favorable time of
year to forecast widespread low stratus.

&&

Preliminary point temps/pops...
dlh 76 59 77 60 / 10 20 30 40
inl 77 56 78 57 / 10 20 40 50
brd 79 64 80 61 / 10 30 30 20
hyr 77 59 77 59 / 10 30 30 30
asx 73 58 77 58 / 10 20 30 40

&&

Dlh watches/warnings/advisories...
Minnesota...none.
WI...none.
Ls...none.
&&

$$

Synopsis...Cannon
short term...melde
long term...melde
aviation...Miller

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