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fxus63 kmpx 201117 

Area forecast discussion
National Weather Service Twin Cities/Chanhassen Minnesota
617 am CDT Thu Jun 20 2019

Short term...(today through friday)
issued at 453 am CDT Thu Jun 20 2019

Light showers have already began to spread into western Minnesota
this morning, with a widespread area of thunderstorms ongoing
farther west across the central Dakotas into Nebraska. The shortwave
responsible for kicking off this precipitation will continue to
track east this morning. Before shunting off to the north as it
pivots around the base of a trough digging into the northern
rockies. This will rob these showers and thunderstorms of their
upper level support as they spread east through the day, with the
bulk of the activity expected to dissipate as it reaches the I-35
corridor later this afternoon. It'll rain across western and west-
central Minnesota but continued the trend of having pops diminish to
around 30-40% across eastern Minnesota as any remaining activity
should be pretty well scattered. Precipitation amounts look to be
fairly light with the upper level support weakening during the day,
amounts of 0.25-0.5" are generally expected across western and west-
central Minnesota

Tonight looks fairly quiet as precipitation from earlier in the day
totally dissipates, and 8a brief period of shortwave ridging builds
into the region. A few spotty showers are possible overnight on the
nose of a low-level jet and increasing warm-air advection, but at
speeds of only 15-20 kts forcing does not look strong enough to
generate off anything widespread. However, the low level jet really
strengthens through the day on Friday in response to cyclogenesis
over the northern plains, with a fairly strong cap building over the
region by Friday afternoon. This cap will influence how early we may
see another round of showers and thunderstorms tomorrow, as a second
shortwave pivots around the trough. Guidance has trended stronger
with the cap this evening with precipitation now likely holding off
until Friday evening, if storms are even able to initiate this far
north at all. The best instability is expected to remain south
across NE/IA, but MUCAPES of 1000-2000 j/kg nosing up into western
Minnesota and 30-40 kts of effective bulk shear suggest at least a
conditional thereat for severe weather from southern into western

Temperatures will remain fairly steady today and tomorrow with highs
in the mid-upper 70s and lows in the mid 50s to low 60s. Humidity
will be noticeable on the rise however as dewpoints generally in the
50s today increase into the upper 50s and low 60s by tomorrow
afternoon thanks to increasing southeasterly winds. Wind speeds will
increase to 10-20 mph this afternoon and become even stronger on
Friday with gusts up to 25-30 mph expected.

Long term...(friday night through wednesday)
issued at 335 am CDT Thu Jun 20 2019

The occluded front will slowly push east Friday night and could
stall over eastern Minnesota Saturday and Saturday night as a secondary
low pressure tracks northeast along it. Showers and thunderstorms
across western Minnesota Friday will build east with the front Friday
night and Saturday. The severe threat by Friday night should be
waning as the activity pushes into increasing heights. The very
impressive eml to the south will lift north some Saturday, along
with the secondary low by Saturday night. This could rejuvenate
some convection across southern Minnesota into WI, but extensive cloud
cover should limit that potential. Another low ejecting from the
trough over the western U.S. Will pass to the southeast of the
area Sunday night into Monday night, keeping the shower and
thunderstorm chances around.

The early week system will be the last of the energy from the
western trough and ridging will quickly build over the central
U.S. During the middle to latter parts of next week. The degree to
how much heat and humidity will increase will depend on where the
ridge center sets up. The GFS is a bit more aggressive than the
ECMWF, eps, and gefs with heights over the Great Lakes region.
However, most of the guidance largely maintains northwest flow and
a stormy ring of fire pattern from the Dakotas into the Great


Aviation...(for the 12z tafs through 12z Friday morning)
issued at 617 am CDT Thu Jun 20 2019

Showers and thunderstorms will continue to spread east across
Minnesota this morning, but are expected to dissipate later this
afternoon as the enter central and eastern Minnesota. Feel
confident in precipitation falling at axn/rwf/mkt, but still
uncertain whether it holds together long enough to impact stc/msp.
Activity would be fairly scattered by the time it reaches eastern
Minnesota so kept a vcsh going to cover this threat. Ceilings will
lower as the day progresses, with MVFR ceilings and visibilities
expected in areas that see rain, and VFR further east.
Light easterly winds become southeasterly through the morning,
with speeds increasing to around 10 kts, with higher speeds and
gusts up to 20 kts at western and central Minnesota terminals.

Kmsp...precipitation looks to dissipate right as it enters the
Metro later this afternoon. Continued the vcsh mention to cover
any scattered showers that may still approach the terminal.
Southeasterly winds will increase to around 10 kts today, with
some gusts around 20kts developing by Friday morning.

/Outlook for kmsp/
Fri...VFR. Rain showers/tsra/MVFR likely late. Wind southeast 10g20 kts.
Sat...MVFR likely. Chc shra/tsra. Wind southeast 5-10 kts.
Sun...VFR. Chc MVFR/shra/tsra early. Wind SW 5 kts.


Mpx watches/warnings/advisories...

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