Drought in Iowa, September 1 to 30, 2023

Area Forecast Discussion
National Weather Service La Crosse WI
1124 PM CDT Thu Aug 31 2023

.DISCUSSION...(This evening through Thursday)
Issued at 254 PM CDT Thu Aug 31 2023

Key Messages:

 - Longer stretch of 90+ temperatures this weekend into next week.
   Sunday and Monday will be the warmest days with highs in the
   upper 90s with a few locations capable of reaching 100.

 - Low relative humidities, increasing winds, and hot temperatures
   will lead to elevated fire weather concerns tomorrow through
   the holiday weekend.

HOT, DRY WEEKEND AHEAD:

With a ridge deepening into our region and providing warm advection
into the weekend, expect temperatures to rise well into the 90s for
most of the area. Consensus amongst guidance for temperatures on
Saturday/Sunday, aside from the GFS which continues to display its
dry soil bias, show temperatures initially warming into the lower
and middle 90s on Saturday with temperatures warming into the upper
90s, nearing 100 on Sunday. Confidence in seeing triple digit heat
is low at this time when considering the 31.06 EC ensembles have low
chances (10-20%) for portions of our region, mostly in the river
valley areas, reaching 100 on Sunday. Additionally, the
deterministic 31.06 EC shows 925mb temps in the 30-32C range which
would suggest temperatures approaching near daily records once
again. However, with September upon us, our records generally are in
the middle and upper 90s so it will not need to be as hot to reach
record territory. Generally not expecting this stretch of heat to
feel as oppressive as last week when considering the lower
dewpoints. The air temperature will be a more accurate depiction of
how it will feel outside.

Labor Day generally appears to be a similar story to Sunday with
high temperatures in the middle to upper 90s for the region when
considering the 31.00 EC having a bit harder time getting 925mb
temps into the 30C range on Labor Day. However, with slightly
increasing dewpoints and increasing southwesterly flow aloft as the
ridge begins to start its trek eastward, likely will feel comparable
to Sunday.

Heat Advisories may be necessary this weekend due to the prolonged,
multi-day stretch of temperatures in the middle and upper 90s,
particularly for the river valley areas that are more prone to
locally higher temperatures.

LOOKING AHEAD:

As we roll into Tuesday, the aforementioned ridge starts to advect
eastward and an upper-level trough approaching from the west will
put our region into a southwesterly flow pattern into the mid-week.
Confidence is much lower with the long-range deterministic guidance
having different schools of thought on what the upper-level flow
pattern will look like. Tuesday will likely still feature
temperatures well above average.

Preciptiation chances for next week appear contingent on a shortwave
that ride along the west to southwest flow on Tuesday which
deterministic guidance has a wide degree of solutions with it at
this time. Currently have lower precip chances (~30% chance) in
accordance with the NBM, but this will likely change significantly
when the upper-level flow pattern becomes more established.

&&

.AVIATION...(For the 06Z TAFS through 06Z Friday night)
Issued at 1123 PM CDT Thu Aug 31 2023

A shortwave trough will move to our northwest tonight. This system
has very little moisture associated with it, so kept the TAFs
mostly clear through Friday. Some tropical moisture will move into
the area on Friday evening. As a result, a broken cirrostratus
deck was added to the TAF for this time period.

&&

.FIRE WEATHER...
Issued at 254 PM CDT Thu Aug 31 2023

TOMORROW:

Dry conditions continue tomorrow. Relative humidities will likely
fall below 30 during the afternoon, especially east of the
Mississippi River. Surface winds build in from the south-southwest
increasing to 10-15 mph in the afternoon. Temperatures will also be
on the rise and with dry, drought-stricken fuels elevated fire
weather conditions are possible.

THE WEEKEND:

Temperatures continue to climb into the mid to upper 90s this
weekend. Breezy, southwest winds persist during the afternoons. A
slight uptick in moisture to the region should hold minimum relative
humidities above 25 Saturday afternoon, but Sunday will be warmer and
drier with minimum relative humidities in the low to mid 20s likely.
While some uncertainty remains regarding how much moisture is
advected into the region on Monday, elevated fire weather conditions
could continue but the emphasis remains on Sunday. Coordination
between the WI NWS offices and WI DNR will take place in the coming
days to determine if a fire weather watch will be needed.

Enhanced fire safety practices should be utilized during this period
as any wildfires that develop could spread quickly. Continue to
monitor the forecast and information from the local DNR leading into
the Labor Day weekend, especially if you plan on camping.

&&

.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&

DISCUSSION...KAA/Naylor
AVIATION...Boyne
FIRE WEATHER...KAA

Hazardous Weather Outlook
National Weather Service La Crosse WI
331 PM CDT Thu Aug 31 2023

IAZ008>011-018-019-029-030-MNZ079-086>088-094>096-WIZ017-029-
032>034-041>044-053>055-061-011115-
Mitchell-Howard-Winneshiek-Allamakee-Floyd-Chickasaw-Fayette-
Clayton-Wabasha-Dodge-Olmsted-Winona-Mower-Fillmore-Houston-
Taylor-Clark-Buffalo-Trempealeau-Jackson-La Crosse-Monroe-Juneau-
Adams-Vernon-Crawford-Richland-Grant-
331 PM CDT Thu Aug 31 2023

This Hazardous Weather Outlook is for portions of southeast
Minnesota...northeast Iowa and southwest into central Wisconsin.

.DAY ONE...Tonight

No hazardous weather is expected at this time.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday

Record or near record high temperatures are forecast over the
Labor Day weekend and early next week with high temperatures in
the 90s. Heat index values are currently forecast to remain close
to the forecast high temperatures in the 90s.

The combination of hot temperatures, low relative humidities, and
gusty winds will lead to elevated fire weather concerns from
Friday into early next week. Continue to monitor the forecast and
information from the local DNR leading into the Labor Day
weekend, especially if you plan on camping or do any outdoor
burning.

.SPOTTER INFORMATION STATEMENT...

No action needed.

.EMERGENCY MANAGEMENT COORDINATION...

No webinar is scheduled.

Boyne