Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Lincoln Illinois
618 am CDT Mon Mar 17 2014
issued 330 am CDT Mon Mar 17 2014
Short term...today through Friday night
00z models are in fair agreement next few days and used a blend.
A quasizonal upper level pattern to prevail this week with a
couple of fast moving wx systems to bring chance of light rain
showers Tue night/Wed morning and again Friday/Friday night. Nice
warmups ahead of each of these systems with mildest temps on Tue
and again Friday with breezy SSW winds. Colder temperatures ahead
this weekend into early next week and the 8-14 day outlook Mar
24-30 has a 70% chance of below normal temperatures over central
Illinois with 40-50% chance of above normal precipitation. So winter may
not be over with just yet.
Low clouds of 2-2.5k ft have backed up into southeast Illinois toward
I-70 past few hours. These clouds trapped in a low level inversion
with NE flow over central/se Illinois with weak surface high pressure
ridge from the Great Lakes SW into northern MO and se Kansas. 1004 mb
surface low pressure was in NW Georgia and keeping its precipitation se
of Ohio River. Weak high pressure ridge to drift se over central
Illinois by 18z today and helping to decrease low clouds over se Illinois this
morning. A fair amount of sunshine expected today and lighter winds.
Highs 40-45f over most of area with coolest around 40f from I-74 NE.
1000 mb low pressure near the Montana/Canadian border to move into
eastern Iowa by sunset Tue and increase clouds and southerly winds
ahead of it over Illinois with warmer highs in the upper 50s and lower 60s.
Even some mid 60s possible SW of Jacksonville. Models bring strong
low pressure into northern lower Michigan by 18z Wed and swings a cold
front east through Illinois during Tue night. This to bring a chance of
light rain showers with heavier pcpn staying north of central Illinois.
Some light rain showers could linger Wed morning and if they do,
could be cold enough for light snow showers too north of Peoria.
Highs in the upper 40s and lower 50s Wed with breezy west winds
behind cold front. Airmass is more of Pacific than Canadian origin.
Highs in the 50s Thu with developing southerly flow by Thu
afternoon as high pressure drifts east of Illinois. Even milder upper
50s to mid 60s on Friday with breezy SW winds.
Long term...Saturday through Monday
Another surface low pressure takes further south track into
central Illinois by sunset Friday and brings cold front thru Illinois late
Friday into Friday night and brings another chance of rain showers.
Cooler temperatures this weekend and dry weather prevails as
Canadian high pressure settles into the Midwest.
issued 612 am CDT Mon Mar 17 2014
VFR conditions are expected to prevail through this forecast period
(12z tue). High pressure centered to our northeast will dominate
the weather across our area today with some patchy mid and high level
clouds along with light winds this morning, which should shift into
the south this afternoon with speeds around 10 kts. Look for the
winds to back more into a southeast direction overnight with again
speeds of 10 kts or less. Forecast soundings suggest the better
potential for low level wind shear will be just to our west late tonight as a storm
system begins to push into the Central Plains.