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Area forecast discussion 
National Weather Service northern Indiana
658 am EDT Sat Mar 28 2015

issued at 440 am EDT Sat Mar 28 2015

Strong high pressure will be overhead today...and will move
southeast to southern Ohio later tonight as a frontal system
moves quickly eastward through the northern plains. After a cold
start this morning...afternoon high temperatures will rebound
into the upper 30s. While warmer than yesterday...this is still
about 15 degrees below normal for late March. Lows tonight will
dip back into the 20s.


Short term...(today and tonight)
issued at 440 am EDT Sat Mar 28 2015

Extremely dry airmass ovhd today with precipitable water values only a few
hundredths above regional record minima for this time of year.
With shortwave ridging aloft near full insolation potnl will
result and should allow for diurnal plus rebound...hir than
NAM/met MOS with apparent/overtly strong surface based
inversion/stability issues. Preference sided more towards ruc13
offering greater depth/steepness of afternoon lapse rates sfc-8h. With
4-6c moderation of 800 mb temperature profiles...have given slight
nudge to afternoon maximum temperatures/acquiesce to late March solar angle as
core of low level thermal trough continues eastward shunt through lower Great Lakes to
upstate New York/eastern PA later today. Little more than a few high cirrus
clouds later tonight inadvof highly progressive Pacific northwest system moving
into the upper Midwest by daybreak. Again sided slightly warmer with
min temperatures owing to continue low level warm air advection along with uptick in surface gradient
flow by daybreak.


Long term...(sunday through friday)
issued at 440 am EDT Sat Mar 28 2015

An upper level trough of Pacific origin will top the western Continental U.S.
Ridge and move across the forecast area Sunday. The NAM has
trended much warmer in the low levels the past 24 hours...and is
now similar to the GFS. Given the latest BUFKIT thermal
profiles...virtually all of the precipitation should be all rain.
There is an outside chance for a brief period of freezing rain
Sunday morning...but for now have kept freezing rain out due to
uncertainties and very limited duration.

For the rest of the period...two more systems are expected to
transverse the area this upcoming week. The first system should
be very weak and little precipitation is expected. Kept a mention
of a rain and snow mix over northern areas where 850 mb
temperatures will be close to 0c. A stronger upper trough should be
able to tap more moisture with a good chance for rain by
Thursday. The GFS and Canadian extended analogs support
anomalously strong high zonal flow developing late this period
across the Midwest...the upper Midwest and the upper Great Lakes
regions. This should allow temperatures to rise above normal by
the middle of the week.


Aviation...(for the 12z tafs through 12z Sunday morning)
issued at 655 am EDT Sat Mar 28 2015

VFR met conds assured through entire forecast period with extremely dry
conds persisting. Minor detail for weak srly return flow later
this evening/overnight as surface ridge moves into central Appalachia
towards end of forecast period.


Iwx watches/warnings/advisories...
Lm...Gale Warning from 11 am to 5 PM EDT Sunday for lmz043-046.



short term...Murphy
long term...skipper

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