Area Forecast Discussion
Issued by NWS La Crosse, WI
Issued by NWS La Crosse, WI
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776 FXUS63 KARX 110744 AFDARX Area Forecast Discussion National Weather Service La Crosse WI 140 AM CST Thu Dec 11 2025 .KEY MESSAGES... - Winter system today shifting a bit farther southwest and bulk of snow likely away from the local area. Parts of NE IA could still receive an inch or two. - Bitter to dangerous cold moves in for the weekend. High temps in the single digits above/below zero. Coldest Sunday morning. Wind chills from -20 to -35F Sat night through Sun morning. Cold Weather Advisories are expected. Plan now for this cold weekend. - More seasonable temps return for next week with a few non-snowing days too. && .DISCUSSION... Issued at 140 AM CST Thu Dec 11 2025 > TODAY-FRIDAY: a couple more shortwaves provide snow chances - but mostly south/north of the local area. The first shortwave will streak from the PAC NW, spinning across the northern plains and then IA later this afternoon/evening. Upglide on the 280:295K surfaces precede it with good, sloping Fgen from southwest to northeast. QG is disjointed, not vertically stacked nor overly strong. There is a little low level feed of moisture on the southern flank of the system with ample saturation per forecast soundings, RH fields. Enough pop and saturation to produce another band of snow across parts of the region - with a few inches likely. Where the band lays out is the main question. Ala recent, similar events, the global models (GFS/EPS) haven`t moved much off their original depictions days ago - stretching the snow band from southwest MN, across central IA into central IL. Real good support from their ensemble suites, respectively. Also ala recent events, the CAMS models (namely the RAP and HRRR) shifted north over the past day...but now are trending back southward - more inline with the GFS and EC. Think this is the way to go and will align the snow chances with the global outlay. With that trend, the primary snow band sits just southwest of the local area. 1/2 to 1" currently progged for portions of SE MN, southwest WI. 1/2 to 2" for NE IA...although the probabilities for 2" currently sit at 20%. No need for a winter weather advisory at this time. Will monitor real-time obs along with meso guidance to see if a shift back north might manifest. The second shortwave is progged to drop across portions of northern MN/northern WI Fri/Fri evening. Has some QG convergence through the layers but weak low level warming and no Fgen to speak of. Also, RH isn`t impressive and only meager QPF. All in all, a weaker shortwave but has enough going for it to produce an area of light snow, albeit with minimal amounts. High chances, low amounts favored in this scenario. Current track keeps the higher local chances north of I- 94. > WEEKEND: very cold! Highs might not warm above zero for some. A hefty slug of cold air follows in the wake of the second, more northern tracking shortwave Friday. 850 mb temps progged to fall from around -8 C at 12z Friday to -20 C by 18z Sat. NAEFS and EC 850 temp anomalies near -2...and expect these to increase over the next couple days. EFI are on aboard with a strongly anomalous cold outbreak for the weekend. Max and Min Ts range from 0.8 to 0.95 with a non zero SoT. At KLSE, over 75% of the EPS and GEFS members suggest it won`t warm above zero through the weekend. The LREF paints 80-100% chances for -10 F or colder Sunday morning area wide. Brrr indeed. Winds, while not expected to be "strong", could blow from 10 to 25 mph at times Friday through Saturday. This will add a signficiant bite to the already cold conditions. Cold Weather Advisories are likely Sat night through Sun morning. A streaking ripple in the upper level flow looks to take a similar path as the shortwave this afternoon/tonight - moving southeast out of the northern plains and across IA on Sat. If this track holds, most (if not all) of any impactful snow will stay well south of the local area. Model blend might be a bit too far north with related snow chances but QPF/snow totals hold more southward. Will stick with the blend for the details for now. > NEXT WEEK: pattern shift! Temps more inline with the season return. Not quite as "busy" for snow chances - more dry days. GEFS/EPS shift east an upper level ridge along the west coast as we move into the new week. Excellent agreement in the all the WPC clusters. The ridge doesn`t stay around long, but the upper level flow stays fairly zonal and progressive. The big upshot from all this is a return to more seasonable temps - potentially a few degrees above. Temps could fluctuate a bit more moving into the following weekend, but no signficiant cold (after this weekend) looming on the horizon. As for pcpn chances, looks like we could get a break from the every other day snow makers that have been plaguing the region over the past week or so. Some consensus via a bulk of the ensemble members for a system to traipse across the northern plains/upper mississippi river valley around Thu. Current solutions suggest a stronger system that could pack a punch - for some. A lot to navigate between now and then, with likely shifts in track/timing. A system to keep an eye on. && .AVIATION /06Z TAFS THROUGH 06Z FRIDAY/... Issued at 1144 PM CST Wed Dec 10 2025 MVFR CIGS expected through the overnight for most locations. Areas in central Wisconsin will see some clearing taking place early this morning. There remains some uncertainty if the MVFR CIGS linger through the entire forecast period. During the mid morning and the afternoon, cloud coverage may not be BKN or OVC in the MVFR flight category, however clouds ahead of the next chance of snow filter in during the afternoon and evening and gradually decrease in height towards the MVFR flight category. Have decided to add in a SCT deck at KLSE and KRST for this potential. By the time the evening rolls around, MVFR CIGS are likely to occur again. Light snow will be possible for portions of southeast Minnesota and northeast Iowa this afternoon and evening. With the potential that some light snow could fall further north, have left the PROB30 groups for both KLSE and KRST for the late afternoon/early evening. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...None. MN...None. IA...None. && $$ DISCUSSION...Rieck AVIATION...Cecava