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fxus63 kmpx 171804 
afdmpx

Area forecast discussion
National Weather Service Twin Cities/Chanhassen Minnesota
1204 PM CST Tue Jan 17 2017

Update...

&&

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/European model (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 Continental U.S.. 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. Relative humidity-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
valley.

&&

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

Kmsp...
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.

/Outlook for kmsp/
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.

&&

Mpx watches/warnings/advisories...
WI...Winter Weather Advisory until noon CST today for wiz025>028.

Minnesota...none.
&&

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