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fxus63 kgld 261726 

Area forecast discussion
National Weather Service Goodland Kansas
1126 am MDT sun Mar 26 2017

issued at 1022 am MDT sun Mar 26 2017

Update issued to remove/cancel dense fog advisory for northern
zones away from Interstate 70 based on latest obs trend. Have
kept in mention of patchy fog though for next couple hours.


Short term...(today through Tuesday night)
issued at 341 am MDT sun Mar 26 2017

Forecast concern will be fog and regular precipitation chances
through the period. Satellite showing a somewhat amplified but still
progressive wave train from the Pacific into North America. The flow
remains split over the central portion of the country with the
previous system moving slowly away and next, compact and rather
potent, system moving in from The Four Corners region.

Analysis shows near 100 meter height falls, rather cold air aloft,
and strong pv anomaly with this system however, satellite and upper
air analysis is showing a lot of dry through mid levels in advance
of it. Models started well at mid levels in this complicated/active
pattern with the Canadian, NAM, and ECMWF doing slightly better.
Models tended to start out too cool on the low level thermal field
with the GFS and Canadian doing a little better.

For today/tonight...again initial issue will be the extent and
density of the fog. Most model output started out too low with
dewpoints. Fog and stratus is progressing east. However, it is
moving in a little slower. Guidance is still bringing in fog over
most of the area and based on latest trends that looks good. So will
areas of fog through mid morning.

Models are in much better agreement about compact/potent low
pressure system that will move across southeast Colorado and
southern Kansas through this evening. This patch plus moisture,
lift, and instability forecasts support most of the south/southwest
half of the area light measurable rainfall. South of the Interstate
should see the highest amounts. Theta-E lapse rates supports keeping
embedded thunderstorms within the rain showers. This system and
associated should move out of the area by late this evening.

There is more agreement about the fog tonight. Because of this,
moist ground/air mass, and light wind field, I chose to add patchy
fog across the entire area during the overnight hours.

As the result of the cloud cover, precipitation, and upslope winds,
lowered the high temperatures especially in the southern half.

For Monday/Monday night...patchy fog will end by late morning. After
that expect a decent amount of sun to occur. Due to light and
variable winds/lack of mixing due to the surface ridge moving
across, chose to lower the high temperatures a few degrees.

Conditions remain dry through the evening. However, beginning after
midnight, a prolonged wet period will begin. Next upper system moves
to just west of the area by late in the night, and will start
pulling in a warmer and more moist airmass. Right rear quadrant may
also affect the far north and northwest half of the area in the
latter half of the night. Kept what the builder gave ME which is a
slight chance to chance of rain.

For Tuesday/Tuesday night...upper system moves little and will
remain to our west and southwest. This will continue to allow a deep
moist air mass to get pulled into the area. Precipitable water
values will be near 0.75 inches which is near 3 Standard deviations
above normal. Large scale mid and upper level lift will bring
widespread rain to the area. Occasional more intense periods will
occur when the stronger mesoscale lift moves across but that will be
hard to time. For the day, conditions will be unfavorable for
temperatures to warm. So I lowered high temperatures from what the
builder gave ME.

Long term...(wednesday through saturday)
issued at 206 am MDT sun Mar 26 2017

Wednesday and thursday: much better model agreement compared to
yesterday at this time with regards to a cut off low that will
traverse the region to our south. The low remains nearly stacked
from 500 mb to 700 mb with an axis of instability stretching from southeast
to northwest ahead of it. Ongoing widespread showers and maybe a
thunderstorm or two are expected through the day on Wednesday, into
Wednesday night and into Thursday. We could see a brief change over
to snow in the eastern Colorado counties before changing back to
rain after sunrise on Thursday. Overall, light to moderate showers
will prevail both days with initial quantitative precipitation forecast amounts near to just over
one inch, especially in areas south if Interstate 70. Precipitable water in the
region will be in the 0.70in to 0.80in range with fully saturated
profiles both days. Winds with this system will become gusty mainly
on Wednesday with the better chances of 30 plus mph wind gusts
remaining in the southwestern portions of the County Warning Area. Temperatures will
reach the lower 50s on Wednesday with upper 50s expected Thursday.
Lows will fall into the lower to middle 30s.

Friday through sunday: dry weather is expected Friday in the wake of
the Wed/thurs system. Shortwave ridging, albeit short lived, will
prevail through the day as another system approaches from the west.
This next system will bring another chance of rain to the region on
Saturday and sunday; however, it will be located a bit further
southwest than the last system with much lower rainfall totals
expected. Highs Friday and Saturday will be near to slightly above
average with widespread upper 50s to lower 60s expected. Lows will
fall into the middle to upper 30s.


Aviation...(for the 18z tafs through 18z Monday afternoon)
issued at 1126 am MDT sun Mar 26 2017

For kgld...MVFR/IFR mix thru 23z Sunday with ceilings bkn005-025.
6sm in light showers and fog. After 23z...VFR thru 06z Monday.
From 06z-14z...MVFR/IFR fog with visibility down to a range of 1
1/2sm to 5sm at times. By 14z Monday...VFR. Winds...east-northeast around
10kts thru 06z Monday with a transition to west-southwest around 5-10kts by
12z Monday.

For kmck...MVFR/IFR mix thru 03z Monday with ceilings bkn008-015
and light showers or sprinkles. From 03z-08z VFR. From 08z to 15z
Monday MVFR/IFR mix in fog with visibility 1 1/2sm to 3sm at
times. VFR from 15z Onward. Winds east-northeast around 10kts thru 03z
Monday...then becoming light and variable.


Gld watches/warnings/advisories...
Kansas...dense fog advisory until noon MDT /1 PM CDT/ today for

Colorado...dense fog advisory until noon MDT today for coz091-092.



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