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Area forecast discussion 
National Weather Service northern Indiana
341 am EDT Wednesday Jul 1 2015

issued at 336 am EDT Wednesday Jul 1 2015

High pressure will slowly build into the region over the next
couple of days bringing a temporary end to the wet conditions that
will last into Friday and possible parts of the weekend. Highs
today will climb into the lower to middle 70s with lows tonight in
the middle 50s.


Short term...(today and tonight)
issued at 336 am EDT Wednesday Jul 1 2015

Mother nature looks to have finally turned off the faucet on the
area as the focus of showers and storms shifts well south of the
area courtesy of high pressure building in from the upper
Mississippi Valley. Until it fully settles into the
region...lingering low level moisture and a few weak disturbances will
cause cloud cover issues...first in the form of stratus...which can
be seen slowly expanding southward from lower Michigan/Lake mi/WI. Have kept
mention of patchy fog for all areas...but backed off "areas" wording
for now. Some mixing will take place through the morning as temperatures
climb into the low to middle 70s for most spots. However...middle level
lapse rates should be just enough to allow for cumulus/stratocu through
much of the day. Backed off somewhat on inland extent for the time
being given several hi res models showing clouds sticking through
most of the afternoon.

Tonight models not in agreement on amount of left over moisture and
subsequent cloud cover. Kept with middle of the Road partly
cloudy/mostly clear as drier air should continue to advect in. Lows
will drop into the middle 50s.


Long term...(thursday through tuesday)
issued at 336 am EDT Wednesday Jul 1 2015

A much welcomed sigh of relief when perusing the 00z nwp suite.
Earlier noted drying trend continues with low level Theta-E gradient
and associated belt of active weather pushing just far enough south
to give our County Warning Area a breather from wet weather through at least the
weekend. Middle/upper level shortwave and associated jet streak will
dig into the high amplitude trough over the eastern Continental U.S. On
Thursday...tracking through the southern Ohio Valley per latest
guidance. Meanwhile...shortwave ridging will slide over Ontario with
split flow/weak high pressure nestled across the Great Lakes. This
pattern aloft and associated easterly low level flow should keep
Theta-E trough in place locally with no instability beneath a
moderate subsidence inversion noted around 800mb. Dry conditions
expected to persist everywhere through at least Friday morning with
just partly cloudy skies and high temperatures a pleasant middle to upper 70s.
00z GFS does try to glance our far southern counties with quantitative precipitation forecast
Thursday night but is an outlier in this respect and will be ignored.

Split flow then looks to persist through early next week with temperatures
slowly moderating back to seasonal averages. Did maintain some token
slight chance probability of precipitation in our far southern counties Friday afternoon as
both NAM and GFS suggest midlevel vorticity maximum may pass just far enough
north to drag some slightly better moisture into our southern County Warning Area
with marginal surface based instability and weak cva touching off a
few showers. Have serious doubts precipitation will make it this far north
though given primarily dry easterly flow in both GFS and European model (ecmwf) as
well as weak forcing and low instability. Even if it does...should
be light...scattered...and of little consequence to flooding
concerns. Another ridge looks to build over the Great Lakes later
this weekend and have removed all probability of precipitation based on consensus of latest
global guidance. Even Monday could be dry as latest GFS and Gem
(even European model (ecmwf) to a lesser extent) are all much slower with next cold
frontal passage. Maintained low chance probability of precipitation for Monday but these too
could be cut if slower/drier trend continues. Best chances for rain
dont look to return until Tuesday...allowing plenty of time for
flooding to abate.


Aviation...(for the 06z tafs through 06z Wednesday night)
issued at 120 am EDT Wednesday Jul 1 2015

No changes to 6z tafs with winds slowly decoupling and cross over
temperatures being approached expected at least patchy MVFR fog and
stratus to develop in the 9 to 12z window before quickly burning
off. NAM cumulus rule suggest scattered to maybe broken cumulus development
across much of the area. Exception will be closer to the lake as
lake breeze/shadow develops and works southeast. This may impact ksbn in
the 21 to 00z window allowing somewhat quicker clearing.


Iwx watches/warnings/advisories...


short term...Fisher
long term...agd

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