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Area forecast discussion 
National Weather Service quadrant cities Iowa Illinois
302 PM CDT Tuesday Jun 2 2015

issued at 240 PM CDT Tuesday Jun 2 2015

12z upper air analysis has a near stationary 850mb high over the upper
Great Lakes into the lower Mississippi Valley. Satellite trends
through middle-afternoon shows low clouds from eastern Missouri into
the southern half of Iowa with some high clouds along the
Mississippi River.

18z surface analysis has high pressure from the Great Lakes into the
lower Mississippi Valley. Dew points were in the 40s across the
Great Lakes and upper Midwest with 50s and 60s from the Ohio Valley
into the plains.


Short term...(this evening through wednesday)
issued at 240 PM CDT Tuesday Jun 2 2015

Quiet and pleasant conditions will again be seen late this afternoon
through tonight as high pressure slowly drifts into the eastern
Great Lakes.

On Wednesday clouds will be on the increase as the next storm system
slowly approaches from the plains. Dry conditions will be seen
during the morning hours with showers and some thunderstorms slowly
overspreading the western third or so of the area by late afternoon.

Cloud cover on Wednesday may suppress temperatures in some areas
with readings slightly below normal.

Long term...(wednesday night through tuesday)
issued at 240 PM CDT Tuesday Jun 2 2015

Near normal temperatures with moderate chances of showers and storms
late this weekend into early next week.

Long term forecast confidence assessment...average to above average
or fair to good. Main issues are normal minor bl relative humidity issues that tend
to be too moist and too cloudy and timing and coverage of precipitation
events Thursday night through early next week.

Overview...moderate variances in solutions with run to run variance
and initialization and verification suggesting a 50/50 mix of GFS and
European model (ecmwf). Poor confidence on timing of storms but all solutions suggest
lower end instability and forcing shear for low to none chances of severe
weather and significant heavy rains with best risks to our SW
days through 7.

Days 2 through 7...consistent pattern of low to moderate chances of
showers and storms each day. Low to moderate instability of at or below 1500
j/kg and low shear and forcing support minimal or no chances of severe
storms. Local precipitable water values between 1.25 to 1.75 inches do support locally
low end heavy rains but best moisture and forcing is to our SW. Temperatures
should be consistently near normal with moderate humidity. Highs upper
70s to middle 80s and mins upper 50 to mostly lower to middle 60s. Chance
of a mesoscale convective system system with front this weekend to locally keep highs some locations
in the low to middle 70s. This should be better known in the next 24


Aviation...(for the 18z tafs through 18z Wednesday afternoon)
issued at 1234 PM CDT Tuesday Jun 2 2015

VFR conditions are expected through 18z/03 as high pressure over
the Great Lakes slowly moves toward the East Coast. Although not
included in the 18z tafs...there is a very real possibility of
MVFR conditions developing around sunrise and continuing through
15z/03 with moisture trapped under an inversion.


Dvn watches/warnings/advisories...



short term...08
long term...Nichols

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