000
FXUS63 KDVN 171949
AFDDVN

Area Forecast Discussion
National Weather Service Quad Cities IA IL
249 PM CDT Wed Apr 17 2024

.KEY MESSAGES...

- There is a marginal or level 1 out of 5 risk for severe
  thunderstorms in far southeast Iowa, northeast Missouri and
  west central Illinois on Thursday. The main threat would be
  hail up to the size of quarter.

- Frost/freezing temperatures possible later this week into the
  weekend.

- Chance for rain early next week and milder.

&&

.SHORT TERM /THROUGH THURSDAY/...
Issued at 201 PM CDT Wed Apr 17 2024

A closed upper level low and its surface low continue to lift
northeastward into the Upper Great Lakes with high pressure
building into Nebraska and Kansas. Winds remained gusty at 2 PM
and were generally westerly at 20 to 25 MPH with gusts up to 40
mph. Temperatures ranged from 52 degrees at Dubuque to 63
degrees at Keokuk.

High pressure is forecast to quickly move across the area
tonight. This will allow winds to quickly drop off overnight
with winds becoming light and variable. Low temperatures on
Thursday morning will range from the mid 40s north of Interstate
80 to the lower 50s in far northeast Missouri.

As high pressure exits to the east, another shortwave moving
through the flow overspreads the area from 9 to 18 UTC from east
central into west central Illinois. CAPE will build northward
into southeast Iowa, far northeast Iowa and west central
Illinois and far northeast Missouri to a few hundred J/KG with
0 to 6 km shear around 50 knots. Think that a line of storms
will develop during the early morning hours and dive
southeastward along the CAPE gradient into northern Missouri
and central Illinois. This seems most likely if storms develop
near the warm front in far northern Missouri or precipitation
will be forced by an frontogenetical band associated with
another cold front that will move across the area Thursday
morning. Models also show scattered showers developing behind
this initial line of storms and continue through the remainder
of the day. High temperatures on Thursday will be cooler and
range be in the mid 50s. It remains to be seen which solution
will win out.

&&

.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
Issued at 201 PM CDT Wed Apr 17 2024

Thursday night through this weekend: Deepening trough in the Great
Lakes region will send rather chilly temperatures into our forecast
area, due to a northwest flow aloft. H8 temps drop to -4 to -6C
allowing for several days of below normal temperatures. With the
recent green-up and sensitive flowers the potential for a frost or
freeze will need to be monitored for headlines. The NBM continues to
show a 50-80 percent probability of freezing temperatures,
especially in our northern counties. However, our entire area is
vegetation susceptible. Lows Thursday night, Friday night, and
Saturday night look to be in the upper 20s to lower 30s north to the
mid to upper 30s south. Highs will be in the 50s.

Early next week: Milder with a zonal flow with another disturbance
in the flow bringing a round of showers on Monday into Monday night.
Highs will be in the 60s.

&&

.AVIATION /18Z TAFS THROUGH 18Z THURSDAY/...
Issued at 1237 PM CDT Wed Apr 17 2024

MVFR ceilings continue early this afternoon as a storm system
continues to slowly exit to the northeast. High pressure
building into the area for this afternoon into tonight will
allow skies to clear from west with VFR conditions expected at
all TAF sites by mid to late afternoon. A second storm system is
forecast to bring scattered showers to all TAF sites from
northwest to southeast from 9 to 15 UTC and continue through
the remainder of the period. Thunderstorms are possible
primarily for  KBRl but confidence is low that they will occur.
MVFR conditions are possible at all TAF sites with the showers.

&&

.DVN WATCHES/WARNINGS/ADVISORIES...
IA...None.
IL...None.
MO...None.

&&

$$

SHORT TERM...Cousins
LONG TERM...Haase
AVIATION...Cousins