336 
FXUS63 KMPX 081205 AAA
AFDMPX

Area Forecast Discussion...UPDATED
National Weather Service Twin Cities/Chanhassen MN
705 AM CDT Fri Oct 8 2021

.SHORT TERM...(Today through Saturday)
Issued at 419 AM CDT Fri Oct 8 2021

Light showers have begun filling in just east of the I-35 corridor 
early this morning as frontogenesis tightens up a bit in the presence
of very meager instability. The showers will likely continue for much
of the day (at least over WI) until the upper low begins to shift 
east this afternoon. PoPs will be updated shortly to increase them to
80-100 percent since the rain has become more widespread than 
earlier anticipated. Amounts will be light, but a quarter inch can't 
be ruled out in some places if the heavier bands remain nearly 
stationary for an amount of time.

Farther west, clouds are more scattered and fog has gotten more 
widespread. Visibilities are generally in the 2 to 4 mile range, but 
some locations have dropped to less than a mile. Not expecting 
widespread dense fog with the high cloud cover and light southeast 
wind, but there could be some local 1/4 mile reports early this 
morning.

Clouds will decrease later today from west to east today as the low 
heads east. Highs should reach near 80 across western MN, but remain
in the 60s over WI where clouds and light rain will continue for 
much of the day. Instability will remain tonight and a few showers or
thunderstorms could develop overnight within the warm air advection
regime, most likely across central MN. 

On Saturday, a surface low will deepen and track toward the eastern
Dakotas late in the day. Moist southeast flow ahead of a cold front
and temperatures rising well into the 70s should provide sufficient
instability for thunderstorm development late afternoon. The strength
of the capping remains the wild card and will ultimately dictate how
widespread they will become. 30-35 kt of deep layer shear could
organize some of these storms to severe levels. SPC has upgraded the
risk to Slight for a portion of west central MN.

.LONG TERM...(Saturday night through Thursday)
Issued at 419 AM CDT Fri Oct 8 2021

Showers and thunderstorms will be ongoing Saturday night as the 
first of three systems during the long term period moves across the 
Upper Midwest. The highest impacts from the first will be felt 
across western and central Minnesota where a few strong to severe 
storms will be possible early Saturday night. Aloft, an upper low 
will track across the eastern Dakotas and northwest Minnesota 
overnight with a strong 250mb jet rounding the bottom of the low. 
Ample shear is evident in large, curved hodographs from forecast 
soundings Saturday evening into the overnight hours across central 
Minnesota. At the surface, the low continues to track across far 
northwestern Minnesota and the associated cold front will move 
across the MPX area. Shower activity will hang around into Sunday 
with winds becoming gusty out of the west by midday. Drier air moves 
in late Sunday with rain ending overnight. 

The break in the showers will be short-lived as our next system 
approaches from the southwest Monday evening. This second storm 
continues to show an eastward trend as mentioned in the previous 
discussion. It's likely that the MPX area only sees a few hundredths 
to a tenth of an inch of rain across our easternmost row of counties 
as we sit on the far northwestern edge of the surface low. Showers 
should come to an end by Tuesday morning as the system tracks 
across the Great Lakes.

Attention then shifts to the third and likely most impactful system 
of the long term period. A strong upper low will lift out of the 
Four Corners region late Tuesday night with a developing surface low 
moving across the Central Plains. The exact track and timing of this 
feature are still uncertain at this point, but a large area of 
precipitation is likely across the Upper Midwest. Introduced thunder 
chances area wide with the trough becoming negatively tilted and a 
highly sheared environment likely. Following the passage of this 
final system, temperatures look to finally settle down closer to mid 
October normals with highs in the upper 50s/low 60s and lows in the 
40s as we head into the end of the week.

&&

.AVIATION...(For the 12Z TAFS through 12Z Saturday morning)
Issued at 705 AM CDT Fri Oct 8 2021

VLIFR conditions across western MN in fog with IFR conditions farther
east across eastern MN and WI with some showers. The fog should
improve slowly this morning but IFR cigs could linger into early 
afternoon. By mid afternoon, clearing will advance northeast fairly 
quickly. Some deterioration back to IFR conditions possible tonight 
across central MN and western WI.

KMSP...Conditions at the terminal have been better than surrounding
areas, but the cig should settle around 1500 ft for much of the 
morning. Once the low levels begin heating and mixing, the cigs
should dissipate this afternoon. 

/OUTLOOK FOR KMSP/
Sat...VFR. Chc afternoon/evening TSRA. Wind SE 10-20 kts. 
Sun...VFR. Chc SHRA. Wind SW 10-15 kts.
Mon...VFR. Chc SHRA. Wind W 5 kts bcmg NE.

&&

.MPX WATCHES/WARNINGS/ADVISORIES...
MN...None.
WI...None.
&&

$$

SHORT TERM...Borghoff
LONG TERM...Dye
AVIATION...Borghoff