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000
FXUS63 KDVN 132353
AFDDVN

Area Forecast Discussion
National Weather Service Quad Cities IA IL
653 PM CDT Sat Apr 13 2024

...00z Aviation Update...

.KEY MESSAGES...

- Well above normal temperatures can be expected through the
  middle of next week, with temperatures increasing into the
  80s!

- Dry conditions through the weekend, with chances for strong to
  severe storms, as well as heavy rainfall Monday night through
  Tuesday.

- Cooldown expected after the Tuesday system, bringing us back
  closer to seasonal norms. CPC favors below normal temperatures
  after the middle of next week.

&&

.SHORT TERM /THROUGH SUNDAY/...
Issued at 215 PM CDT Sat Apr 13 2024

Another beautiful day is being seen throughout, with temperatures in
the mid 70s. Coupled with these unseasonably warm temperatures are
no clouds, giving us full sun. Breezy southerly winds will continue
into the nighttime hours, waning down from west to east. A cold
front will pass through tonight, shifting winds northwesterly and
allowing speeds to decrease throughout. Moisture will be limited
ahead of this wave, leading to a dry frontal passage. Although, some
midlevel moisture will allow for clouds to develop, but will clear
out for many by sunrise.

Tomorrow, we will see a repeat of today, with even warmer
temperatures expected. Many locations will see around a 10 degree
increase compared to today. Thus, much of the area will be in the low
80s. Cloudless skies will dominate tomorrow, with the main
difference in the forecast being the lighter winds. We are expecting
northwest winds around 5-10 mph.

Get out and enjoy the weekend!

&&

.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
Issued at 215 PM CDT Sat Apr 13 2024

High pressure will slowly traverse through the north this weekend
and into early next week, prior to the next wave set to impact our
area. With high pressure being overhead, the remainder of the
weekend and into Monday will be quite warm and beautiful, with
temperatures in the 80s. This increase in temperatures is resulting
from strong warm advection into the region, being enhanced by the
approaching wave. Much of the moisture transport will not be seen
until Monday and Tuesday, where we will start to see clouds push in
Monday, with thunderstorms expected that night and through Tuesday.

Monday night and through Tuesday will be a timeframe to keep in
mind, as confidence is increasing in the potential for strong to
severe thunderstorms. Guidance is in relatively good agreement on
this system, with minimal differences. In either case depicted by
deterministic/ensemble guidance, we will still see the potential for
strong to severe thunderstorms. There will be two rounds of
thunderstorms with this system, which will both have severe
potential, as well as heavy rain. Current WPC guidance hits the
rainfall better than some of guidance, coming in a little higher
than most. Looking into the model soundings, PWATS will range
between 1.25-1.50"+, which is above the daily climatological max
locally. Diving into probabilities, areas along and north of
Interstate 80 have a 70-90% chance of seeing at least 0.50" of
rain, with the chances for 1.00" or more ranging between 40-60%.
These totals are around the 75th percentile of guidance. Given
that moisture availability is nearing maximum amounts for this
day, I think the higher ranges that we are advertising are a bit
closer to what we may see in reality. Granted, much can change
over the next 48-72 hours, but given such agreement, substantial
changes aren`t expected at this time. In either case, this
heavy rainfall will be widespread and may lead to rises in local
streams, as some are already higher than normal.

The first wave to come through will be Monday night, as we see a
strong push in warm advection, with the warm front pushing north
through our area. This will be a focus for convection, as a strong
LLJ will pump into this frontal boundary, with plenty of lift to see
nocturnal thunderstorms develop. Overall, instability is lower,
generally hovering between 500-1000 J/kg. Shear and lapse rates
will be more than sufficient to favor a few elevated strong to
severe thunderstorms. As is usually the case with nocturnal
thunderstorms, we will likely be dealing with hail potential and
frequent lightning. Later in the day Tuesday, our forecast area
will fall under the warm sector of the advancing surface low.
In the warm sector, we should see moderate instability build,
given nocturnal convection and cloud debris move out in the
morning. Moderate-High deep layer shear will balance out with
the instability to result in an environment favorable for
organized convection, some of which may be severe. Currently,
guidance is showing the chance to get a line of severe storms,
with the environment favoring some embedded supercell
structures. The timing is Tuesday afternoon and evening, but
there is plenty of time of this to change. Given we are 3 days
out still, many details are still unknown. Through the coming
days, we will get a better idea of the environment in place,
given more short term guidance being ingested. The SPC continues
to highlight our whole area in a Day 4 Slight Risk for severe
weather (level 2/5). Again, just keep this day in mind and take
any necessary precautions.

After this system passes, we will see a cooldown at the end of the
week and into the weekend, bringing us closer to seasonal norms.
Through the long term, we will likely see our share of windy days in
the mix as well, especially Tuesday. The CPC favors below
normal temperatures after midweek and into the weekend.

&&

.AVIATION /00Z TAFS THROUGH 00Z MONDAY/...
Issued at 650 PM CDT Sat Apr 13 2024

A VFR TAF cycle through Sunday evening, with passing patches of
mid and high clouds. The main impact will be turbulent low to
mid levels tonight as a southwesterly LLJ at 2K FT AGL ramps up
to 45-50 KTs. Will maintain LLVL wind shear tonight into early
Sunday morning at all sites, despite southwesterly sfc winds
maintain 10-15 KTs with higher gusts. Sunday morning a passing
sfc trough will veer the winds to the west and then to north-
northwest during the late morning into the afternoon.  ..12..

&&

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

&&

$$

SHORT TERM...Gunkel
LONG TERM...Gunkel
AVIATION...12