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Area forecast discussion
National Weather Service Grand Forks ND
653 am CDT Mon Aug 19 2019

issued at 653 am CDT Mon Aug 19 2019

Still have a few echoes up around the Lake of The Woods region. As
these echoes moved over the Roseau Airport, some light rain was
reported. Therefore updated the forecast to add in a mention of
isolated showers for a few more hours. No other changes were
needed to the forecast at this point.


Short term...(today and tonight)
issued at 409 am CDT Mon Aug 19 2019

There are currently a few echoes up along the Canadian border,
moving into northwest Minnesota. However, surface observations are
showing the clouds to be pretty high based, so doubt much of
anything there is actually reaching the ground. Will continue to
keep an eye on observations and see if the dry trend there
continues. Temperatures are holding up much more than last night
at this time, but surface dew points are still on the low side.
Southerly flow today should help in the moisture return, but not
quite sure if near 70 afternoon dew points are possible across the
far southern forecast area. Do expect to see quite a bit of sun again today,
with high temperatures about 10 degrees warmer than yesterday
(back into the 80s). Not expecting any precipitation in this forecast area
during the afternoon hours either.

Starting to see a little better definition in regard to
precipitation chances tonight. Again, do not think much will
affect this forecast area until mid to late evening, and even more so after
midnight. By 10 PM this evening, models show a weak surface low
over northwest or north central North Dakota. Decent instability
will exist ahead of this low, which looks to track eastward into
this forecast area overnight. Models are showing a better defined low level
jet ahead of this boundary as well, although its focus appears to
be a little better into southern Manitoba and southern Ontario.
There is also good low level warm advection and 0-6km effective
shear. So if storms can fire along the surface low/boundaries
across the western half of North Dakota during the mid evening,
they should be able to hold together as they move eastward

Still uncertain whether these storms will be severe as they reach
this forecast area. Also uncertain about where these storms may be. Some high
resolution models show better chances across the north, some in
the central, while others show the potential in the southern forecast area.
Storm Prediction Center did keep the entire forecast area in a marginal risk, so can't completely
rule the severe storm potential out. Due to the time of night the
storms would be in this fa, agree the severe chances are low.
However, chances are looking better now than they did yesterday
for seeing at least some strong storms holding together as they
reach this fa, just not sure where or how many at this point.
Pretty hard not to keep at least an isolated or scattered mention
everywhere from late evening through the overnight hours.

Long term...(tuesday through sunday)
issued at 409 am CDT Mon Aug 19 2019

Storms should be exiting the eastern forecast area on Tuesday morning. In the
wake of the cold front, north winds look to become pretty gusty by
Tuesday afternoon.

For Tuesday through Thursday, quiet and cooler weather develops as
strong surface high pressure builds into the northern plains from
Saskatchewan and dry northwest flow aloft persists behind an upper
low near Hudson Bay. This pattern will yield dry weather with daily
high temperatures in the 70s and overnight low temperatures in the
40s to lower 50s. By Thursday, the influence of the upper low over
the Hudson Bay gives way to weaker ridging aloft across the northern
plains, but warmer southerly flow has little time to become
established before the next disturbances begin to advance into the
plains heading into the weekend.

For Friday through next weekend, chances for showers and storms
develop as a shortwave trough aloft intensifies over the Canadian
prairie, ahead of an approaching robust longwave trough advancing in
from the Pacific. This activity brings the next best chance for
precipitation in the late Thursday night through Friday night time
frame as another frontal boundary is poised to advance west to east
through the northern plains. Although confidence in any details is
low at this time, this frontal passage and additional disturbances
aloft prompt potential for off and on thunderstorm chances through
the weekend.


Aviation...(for the 12z tafs through 12z Tuesday morning)
issued at 653 am CDT Mon Aug 19 2019

There will likely be few-scattered VFR cumulus around again this
afternoon. Think the thunder chances will start after 03z tonight,
continuing into early Tuesday morning at taf sites along and east
of the Red River. Confidence is still pretty low that storms will
hit any one taf site, but wanted to give a best possible timing
estimate, so used the thunderstorms in the vicinity for this. Overall, expect a lot of
variation in wind directions throughout the 24 hour period, but
not too much for speeds.


Fgf watches/warnings/advisories...


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