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FXUS63 KMPX 171804

Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
1204 PM CST Tue Jan 17 2017



.SHORT TERM...(Today and tonight)
Issued at 410 AM CST Tue Jan 17 2017

It will be an icy start to the morning for much of east central
Minnesota and west central Minnesota, especially on untreated
roads/pavement. Due to the current road conditions, combined with
the lingering snow/sleet/freezing rain mix that's ongoing from the
Twin Cities metro north along the Interstate 35 corridor and east
into west central Wisconsin, have extended the advisory through
the morning commute. 

By the noon hour, the responsible shortwave will have shifted
southeast of the forecast area, so precip should follow suit and
come to an end in west central Wisconsin. Clouds will linger a bit
longer, especially over eastern areas. Temperatures will remain
mild, with highs in the mid 20s to mid 30s and lows from 15 to 20. 

.LONG TERM...(Wednesday through Monday)
Issued at 410 AM CST Tue Jan 17 2017

The main story in the extended has not changed much, it's the 
prolonged January thaw expected the rest of this week through 
the weekend. Although the forecast has a lot of precip chance 
mention from Friday on, we are not anticipating any significant 
precip makers to impact the region through Monday.

Through the extended, the GFS/ECMWF do not differ much on the large 
scale pattern details, which still looks to feature a blocking high 
building out of the Atlantic across eastern Canada while a series of 
storm systems crashing ashore the Pacific coast will slowly build a 
deep trough across western North America. This pattern will result 
in a pronounced split in the flow, with the northern stream 
displaced well to the north across central/northern Canada while the 
southern stream goes across the southern CONUS.  Where differences 
in details start to show up is with how some of the southern stream 
will get ejected up this direction this weekend into next week.

We continue to have high confidence in a prolonged stretch of warm 
weather with highs in the mid 30s/lower 40s from Wednesday through 
Monday. That's the good news, the bad news is this is a January 
thaw, not a March thaw, which means come Wednesday night, this 
stretch of warm weather looks to feature ample stratus and fog, not 
bright sunshiny days. RH-time heights from the GFS highlight this 
well, with low level saturation moving in Wednesday evening, with 
the low levels remaining saturated for the next several days. So it 
will be warm, but with a side of permacloud. What this warmth and 
cloud cover will mean is very little in diurnal temperature ranges, 
with ranges of just 5 degrees looking to be tough to come by once 
the clouds set in.

For precip, this forecast is unfortunately full of it from Friday 
on, though it does not look to be as bad as all of the 20-40 pops 
may imply.  Basically, by Friday, we get into a very moist 
southeasterly low level flow with several disturbances heading our 
way beginning Friday afternoon for our eastern areas. After that, we 
look to get into a showery/drizzly period of weather that will last 
through the weekend. It's not until the middle of next week that a 
more organized system looks to possibly work across the upper MS 


.AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon)
Issued at 1204 PM CST Tue Jan 17 2017

Wintry weather has moved east of western WI this afternoon leaving
borderline IFR/MVFR ceilings for this afternoon. Low clouds have
been stubborn to move out this morning with only AXN free of low
ceilings as of 18Z. Expect ceilings to remain fairly steady 
towards sunset, when clearing and VFR conditions are expected to 
prevail area wide. Northwesterly winds will remain light and back
through this evening, becoming southerly by Wednesday morning

IFR ceilings have stalled just west of MSP, leaving MVFR ceilings
steady at 015-020. Expect some of these lower clouds to stream in
this afternoon but should only be scattered. Clearing to VFR
conditions expected around 00Z with light northwesterly winds 
backing to the south tomorrow morning. 

Wed...VFR. Chc MFVR late. Winds SW 5-10 kts. 
Thu...MVFR. Chc IFR. Winds S 5-10 kts.
Fri...MVFR/IFR. Slight chance -RA. Winds southeast around 5 mph.


WI...Winter Weather Advisory until noon CST today for WIZ025>028.



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