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Area forecast discussion 
National Weather Service Lincoln Illinois
626 am CDT Thu Aug 21 2014

Short term...(today and tonight)
issued at 342 am CDT Thursday Aug 21 2014

Warm front has lifted north through most of the area and based on
surface observations, looks to be just north of I-74 at this point.
Believe the front will continue to lift north through the day,
resulting in the whole County Warning Area being in the warm sector for the end of
the week. However, the mid level ridge will be somewhat flat and any
disturbance or wave that moves along the top of the ridge could
result in precip dropping into the northern and northeastern part of
the County Warning Area. So chance pops will continue to be warranted over parts of
the County Warning Area today and tonight. Pops will be less during the daytime
hours but then increase over the northeastern half of the County Warning Area for
the overnight hours, tonight. Temperatures will be warm today, but
cloud cover could keep afternoon highs from getting too high, though
still expecting highs around 90 today. Lows tonight will be similar
to now, just about 1-2 degrees warmer.


Long term...(friday through wednesday)
issued at 342 am CDT Thursday Aug 21 2014

Summer heat continues through the remains of the weekend. Hot and
humid conditions lending to an isolated thunderstorm threat through
the weekend, particularly towards the NE as waves push over the
upper ridge building into the Midwest. Models shifting with each
issuance as to the actual increased threat with the erosion of the
ridging to the NE. Heat and humidity has been more consistent,
though even that has seen some shifts, starting to retract some of
the eastward creep of the 850 mb temps. Not pulling back too much
in the way of guidance just yet and temps Fri-sun still in the 90s,
heat indices over 100f. Issuance of a heat advisory covered
above...however, should the dwpts materialize, or see the temps
respond as expected behind this mornings warm front today... will
rethink the issuance of a heat advisory for the weekend as these
temps are not only well above normal, but more impactful after such
a mild Summer so far. Into the extended, day 6/just into day 8,
models have gone back to a divergence in solutions as the GFS is
more progressive with the next upper trof moving a cold front
through with storms and cooler temps in the wake...while the 00z
European model (ecmwf) is now cutting off the low over the NW, extending the ridges
hold over the region.


Aviation...(for the 12z tafs through 12z Friday morning)
issued at 626 am CDT Thursday Aug 21 2014

The warm front has lifted north of all the taf sites and all pcpn
has moved north or east of the sites this morning. So most of the
day all sites will be pcpn free. So, there will be some high cumulus/SC
today with some cirrus early and then maybe some ac later this
morning. Then by this afternoon, skies should become scattered.
Clouds will then be on the increase around midnight as a complex
of storms will develop west of the area and move along the warm
front tonight. This should bring broken ac clouds to spi and Dec,
but thunderstorms in the vicinity and broken SC/cumulus at pia/bmi/cmi. Winds will be southwest,
but become southerly this evening for a brief time, then back to
southwest around midnight. Wind speeds will be around 7-10kts
through the period.


Ilx watches/warnings/advisories...


Short term...auten
long term...hjs

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