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fxus63 kmpx 160858 
afdmpx

Area forecast discussion
National Weather Service Twin Cities/Chanhassen Minnesota
358 am CDT Tue Jul 16 2019

Short term...(today through wednesday)
issued at 324 am CDT Tue Jul 16 2019

A frontal boundary was slowly moving southeast across southern
Minnesota early this morning. Although the pressure gradient is
weak, there is enough drier air behind this wind shift to hold off
the recent excessive humidity for most of Minnesota. Therefore, heat
indices will only reach the low to mid 90s, vs the upper 90s to
lower 100s on Monday. This frontal boundary will stall this morning
along the Iowa border. This is where the bulk of the convection will
redevelop this morning, and through the afternoon. Areas from
Fairmont to Owatonna, and southward will have the best chance of
showers and thunderstorms later today. The humidity levels will also
be more noticeable in these areas. Elsewhere, the chances of
precipitation are much lower, and most areas will be dry.

Later tonight, a complex of storms should redevelop across the
Dakotas in response to a potent short wave moving across the Pacific
northwest this morning. This short wave, in combination of the
frontal boundary returning northward, should provide for scattered
showers/storms in western Minnesota late tonight, and across the
rest of Minnesota toward Wednesday morning. There remains some
disagreements in the models on the orientation of the short wave
later tonight. The ec has the bulk of the precipitation in
Nebraska/South Dakota, and moving this area across far southern
Minnesota/Iowa Wednesday. The GFS is farther to the north which
brings heavier, and more widespread precipitation across
central/southern Minnesota on Wednesday. Either way, chances of a
more organized precipitation event on Wednesday is more likely than
today. The chances of severe weather are also better on Wednesday
based on the increasing wind shear as the upper jet moves farther
south across the northern tier of the nation by midweek.

Long term...(wednesday night through monday)
issued at 324 am CDT Tue Jul 16 2019

Upper ridging will retain its grip on the region through Friday,
with hot temperatures again on Friday. However, there is
reasonable model consensus on troughing developing over the region
by the second half of the weekend into next week as upper ridging
develops over the west. This should allow temperatures to return
closer to normal (if not a bit cooler) by early next week. We'll
see some subsidence and drier air work into the area late
Wednesday night and Thursday, but thunderstorm chances will return
Friday afternoon as the warm frontal boundary becomes better
defined across the area ahead of a shortwave trough that will work
through the region Saturday. The guidance is still not in very
good agreement on the timing or amplitude of this feature, which
will impact how long the heat lingers across the region before
significantly cooler and drier conditions arrive. As a a result,
retained some chance pops through most of the weekend, although
Sunday certainly looks like the drier of the two days at this
point.

&&

Aviation...(for the 12z tafs through 12z Wednesday morning)
issued at 355 am CDT Tue Jul 16 2019

Very similar tafs as with the 06z taf issuance as the bulk of the
thunderstorms and rain/rain showers will occur late tonight, especially across western
Minnesota. A few thunderstorms and rain are possible near kmkt later this
morning/afternoon, but believe most of the activity will be south
of the Airport. Light west/northwest wind today, becoming
east/southeast overnight.

Kmsp...

Only change to this taf was to introduce a predominate rain showers/thunderstorms in the vicinity
after 12z Wednesday. This will likely be adjusted as thunderstorms and rain begin to
develop late tonight. Otherwise, no other changes.

/Outlook for kmsp/

Wed aftn/evening...VFR/MVFR with thunderstorms and rain likely. Winds southeast 10 kts.
Thu...VFR. Winds light and variable.
Fri...VFR. Isolated thunderstorms and rain. Winds SW 5 kts.

&&

Mpx watches/warnings/advisories...
WI...none.
Minnesota...none.
&&

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