Rochester, Minnesota 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

526
FXUS63 KARX 101044
AFDARX

Area Forecast Discussion
National Weather Service La Crosse WI
544 AM CDT Tue Jun 10 2025

.KEY MESSAGES...

- Dry and mostly clear today with a narrow band of low
  precipitation chances overnight into early Wednesday morning.

- Strong to severe storms possible primarily in the southern
  half of the forecast area from northeast Iowa into southwest
  Wisconsin Wednesday afternoon/evening. Hail will be the
  primary hazard.

- Heavy rain concerns Wednesday through Friday. Rain sticks
  around through the weekend.

&&

.DISCUSSION...
Issued at 317 AM CDT Tue Jun 10 2025

Dry, Near Seasonable Today, Low Rain Chances Tonight:

Building isoheights through the morning hours with a bout of low
level dry air primarily along the southern half of the forecast area
will provide clear skies for most of the area through today. Strong
WAA through the Rocky Mountain West overnight (10.00Z RAOBs) advects
into the Northern Plains, grazing the western part of the forecast
area. Therefore, highest daytime temperatures locally expected
along western peripheral counties in southeast Minnesota and
northeast Iowa. Should the warm nose poke slightly east, may see
the 80 degree isotherm traverse into central Wisconsin.

Have added a band of light precipitation chances overnight into
early Wednesday morning due to a low level trough tapping into
limited moisture protruding anticyclonically from the
aforementioned increased low level theta e lobe. A transient
plume of sufficient isentropic upglide concurrent with frontal
passage provides sufficient forcing.

Wednesday Storm Threat:

An upper level low slowly shifting east through the Desert Southwest
on GOES water vapor imagery early this morning is expected to
stagnate over the Texas panhandle through Wednesday. This low
invigorates anticyclonically fed tropical moisture through the
Central into the Northern Plains. The resultant atmospheric
river of 1000 J/kg advects anomalous moisture and resultant high
instability towards the forecast area. As the plume of moisture
advects north it eventually meets a dry air appendage from
todays departing extratropical cyclone. Most recent LREF cluster
analysis places this zonal oriented moisture boundary along the
Iowa/Minnesota border with 1500 J/kg+ of instability coexisting with
30kts of 0-500mb of mostly speed shear.

The resultant LREF member plumes exhibit linear hodographs
suggesting multicellular convection near the boundary. Main hazard
will be hail as storms initiate along the axis of convergence
and subsequently lose instability as they head north. Machine
learning algorithms agree with this solution painting 15-25%
probabilities along the southern half of the forecast area.
Besides a secondary damaging wind threat, the near parallel
storm motion in relation to the boundary also raises a tornado
threat as it could provide the required low level circulation.
Quite a conditional threat in a narrow axis as any additional
helicity will be hard to come by.

Heavy Rain Threat Wednesday:

The anomalous moisture abutting a mostly stationary boundary
presents heavy rain concerns. Strong west to east flow will
quickly progress storms parallel to the boundary with downshear
corfidi vectors of 35kts at 270. May see storms repeat along the
same areas due to the frontal boundary remaining steadfast from
mesoscale cold pool reinforcement as storms head north.
Additional forcing of a frontogenetical direct thermal
circulation resultant of ageostrophic direct thermal ascent
from the upper level jet streak situated to the north may also
persist repeating storms along the same narrow axis.

Most recent high resolution forecast soundings (RAP) keep warm
cloud depths marginal (<3km) until overnight into Thursday
morning when they suggest a northern push farther into the
forecast area. Still at lot to work out as exact location of
surface boundary and potential mesoscale reinforcement will
determine location of potential impacts.

Current LREF forecasts call for 25th to 75th percentiles from
0.15" to 1". Fortunately regional soils remain drier.

Precipitation Chances Through Sunday:

A blocking pattern sets up through the week into the weekend as
the aforementioned upper level weak wave sits between and is
fed moisture from anticyclonic flow to its southeast and
southwest. Limited synoptic forcing persists Wednesday`s pattern
and stationary boundary although some fluctuation in main area
of heavier precipitation can be expected due to passing
weakening waves along southwest flow. Highest amounts expected
through Friday with the same 25th to 75th percentile LREF
amounts as Wednesday (0.1" to 1"). Less amounts expected through
the weekend as the main moisture axis shunts east. While
overall flooding concerns aren`t overly high, should a few days
of heavy rain locally or upstream be realized, may need to
remain aware of river levels. Although rivers have room to swell
as levels remain below normal for this time of year.

&&

.AVIATION /12Z TAFS THROUGH 12Z WEDNESDAY/...
Issued at 545 AM CDT Tue Jun 10 2025

As diurnal heating occurs, the low-level inversion near 900 mb
will gradually mix out and the MVFR clouds will become
scattered between 10.13z and 10.15z. With ridging at the
surface and aloft, skies will be mainly mostly sunny today.

Between 11.02z and 11.04z, a mid-level deck between 10-15k will
move into the area from the west.

&&

.ARX WATCHES/WARNINGS/ADVISORIES...
WI...None.
MN...None.
IA...None.

&&

$$

DISCUSSION...JAR
AVIATION...Boyne