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Area forecast discussion 
National Weather Service northern Indiana
324 PM EDT Monday Sep 22 2014

issued at 321 PM EDT Monday Sep 22 2014

A pleasant start to fall as high pressure over the Central Plains
continues to build over the Ohio Valley. This will produce clear
and dry conditions. After a cool start to the day Tuesday...with
lows in the low to middle 40s...daytime temperatures will moderate
through the week with highs warming to the middle to upper 70s by


Short term...(this evening through tuesday)
issued at 321 PM EDT Monday Sep 22 2014

High pressure building across the plains into the Great Lakes will
persist through the short term forecast. Moisture will continue to
decrease through the period and this should be enough to allow for
large diurnal temperature swings.

Otherwise quiet weather.


Long term...(tuesday night through monday)
issued at 321 PM EDT Monday Sep 22 2014

No significant changes to thinking in the long term portion of
forecast with a gradual warming trend and dry weather expected.

Surface high will be east of the area Wednesday but low level
southeasterly flow likely to limit mixing and warming just a bit.
Soundings suggest mixing heights to about 925mb Wednesday and 900mb
Thursday. This yields maximum temperatures generally in the low 70s Wednesday and low
to middle 70s Thursday. Verification statistics for County Warning Area indicates a rather
pronounced warm bias of 1 to 3 degrees with blended data over the
last month. Dropping allblend by a degree or two yields maximum T values
close to mix down values from soundings. Should see temperatures into the
middle 70s by end of week and into weekend. Low temperatures will begin the
period in the 40s but modification will allow mins to rise into the
50s by middle to late week.

Only change seen in latest model runs is with weak short wave energy
approaching Thursday. Previous models were holding staunch middle and
upper level ridge in place. Latest runs suggest this short wave may
make it into western Great Lakes region before being deflected
south. Lower levels remain dry with ridging so at this time only
expect a subtle increase in high clouds as this feature approaches.
Models still indicating some sub tropical moisture and a very weak
middle to upper level system working toward the area this weekend.
However...still does not appear deep enough or close enough to our
area to warrant any pop inclusion. This will be watched in later
model runs for any changes.


Aviation...(for the 18z tafs through 18z Tuesday afternoon)
issued at 321 PM EDT Monday Sep 22 2014

High pressure will dominate the weather for the next forecast
period. A few cumulus have formed over Lake Michigan in convergent
flow...but this cumulus will linger only through early evening. With
the core of drier air overspreading the region expect VFR
conditions througout the period.


Iwx watches/warnings/advisories...
Lm...Small Craft Advisory until 5 PM EDT this afternoon for lmz046.



short term...Lewis
long term...Lashley

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