Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 02/15/20
Area Forecast Discussion...UPDATED
National Weather Service Albuquerque NM
749 PM MST Fri Feb 14 2020
Patchy fog being reported in the Clovis area during the last hour
despite the high clouds. Broad area of mid 30s dewpoints will
continue to be in place from the Pecos Valley south of Santa Rosa and
east to the TX border with a se to south wind. HREF, HRRR and RAP13
suggest there will be low clouds that spread up the Pecos Valley
later tonight, and patchy fog may expand. Therefore added patchy fog
to the wx grids and beefed up cloud cover. Updated ZFP just
.PREV DISCUSSION...443 PM MST Fri Feb 14 2020...
00Z TAF CYCLE
West to northwest flow aloft. Sfc low over se CO at 23Z to shift sewd
and into the TX panhandle by 15/15Z with a corresponding north to nely
wind shift over ne and east central NM. Low clouds which lingered
over portions of the Pecos Valley and through KROW have scattered
out but short term guidance indicates MVFR cigs returning aft 15/09Z
then dissipating by 15/17Z.
.PREV DISCUSSION...236 PM MST Fri Feb 14 2020...
The warming trend will continue through the weekend, with daytime
temperatures reaching above normal areawide by Sunday. Several
locales in the eastern plains will reach into the low 70s Sunday,
where breezy to windy conditions are expected. A strong cold front
will push through late Monday into Tuesday, bringing temperatures
back down below normal and keeping them there through the end of the
work week. Moisture will increase over the state mid week and
interact with a slow moving disturbance, bringing chances for
precipitation back to the forecast. Some improvement is forecast by
Friday as the disturbance moves out and temperatures rebound several
SHORT TERM...(TONIGHT THROUGH SATURDAY NIGHT)...
A weak and flattening ridge will bring in some high clouds from the
west through the overnight hours. A leeside trough over eastern
Colorado will help to strengthen winds along and east of the central
mountain chain through the evening hours. A weak backdoor cold front
will drop into northeast New Mexico on Saturday, lowering
temperatures by a few degrees. Otherwise, the warming trend will
continue through the weekend.
LONG TERM...(SUNDAY THROUGH FRIDAY)...
Sunday will be the warmest day this forecast cycle, with temperatures
rising above normal areawide. This is especially true across the
eastern plains, where highs will reach up into the upper 60s and
lower 70s thanks to stronger downslope winds.
The jet stream will slide south into the southern Rockies on Monday,
bringing a much colder airmass with it going into Tuesday.
Temperatures will dive below to well below normal behind the front
and stay there through Thursday before moderating some on Friday.
There is still plenty of forecast uncertainty with regard to the
development of an upstream upper level trough/low and resulting
precipitation across our area Wed/Thu. The other important and
uncertain factor is a Pacific moisture tap, but the medium range
model solution continue to trend away (further south) from direct
impacts to our area. If the Pacific moisture tap aims a tad further
north, we will be looking at the potential for freezing rain and/or
sleet across much of the southeast plains with significant snow
accumulation in the south central mountains.
The 12Z medium range model solutions show an active troughing pattern
across the western US for late next weekend and into the following
week, so if the mid week event is a dud then we may be set up for
more precipitation in the day 8-10 range.
There are no critical fire weather concerns at this time. The
weekend will be warm with mostly sunny skies, with the exception of
temperatures lowered by a few degrees Saturday with a dry backdoor
cold front across the northeast. Haines values drop from
moderate-high to moderate values by Saturday. Humidity
recoveries will be poor Saturday night into Sunday across the
eastern plains, but minimum RH`s do not reach critical thresholds.
Sunday will be the warmest day of the week, with up to 15 degrees
above normal across the eastern plains. Ventilation rates will be
good by Sunday, with breezy to locally windy conditions along and
east of the central mountain chain. A weak system will clip the
state on Monday, bringing light snowfall accumulations to the
Area Forecast Discussion...UPDATED
National Weather Service Aberdeen SD
914 PM CST Fri Feb 14 2020
Issued at 912 PM CST Fri Feb 14 2020
Conditions continue to improve across the southeastern part of the
CWA as wind speeds diminish, therefore allowed the remaining
portion of the Winter Weather Advisory to expire. No other changes
made to the forecast at this time.
UPDATE Issued at 603 PM CST Fri Feb 14 2020
With diminishing wind speeds and improving conditions, have
allowed the entire Wind Advisory and the Winter Weather Advisory
in Roberts county to expire. Will keep with Winter Weather
Advisory going for Grant and Deuel counties as wind speeds are
expected to stay up there for a few more hours.
.SHORT TERM...(This Evening through Saturday Night)
Issued at 304 PM CST Fri Feb 14 2020
Gusty southerly winds continue impacting the eastern half of the CWA
this afternoon with the highest winds occurring along the I-29
corridor. With the recent light snow, along with the strong winds,
patchy to areas of blowing snow have been observed on webcams,
especially in Summit and Brandt. Winds will slowly diminish from
northwest to the southeast through this evening. Will maintain the
current ending time for the wind advisory, and the winter weather
advisory for Roberts. Based on the latest RAP half KM winds, will
extend the winter weather advisory for Grant and Deuel Counties
until 9 pm.
A weak upper level trough will push across the region tonight, with
increasing mid level clouds and a shift in the wind direction
expected. 925 mb temps will be cooler on Saturday behind the trough,
but favorable mixing winds should produce highs in the upper 20s to
the upper 30s. High pressure sliding southeast across North Dakota
and Minnesota Saturday night will bring cloudy skies, along with
colder temperatures. Lows should drop into the single digits and low
teens above zero.
.LONG TERM...(Sunday through Friday)
Issued at 304 PM CST Fri Feb 14 2020
The long term period opens with a near zonal flow aloft. Weak energy
moving through this pattern does introduce low chances for light
snow Sunday night and Monday, although moisture and lift are
lacking. The blended run tries to introduce a loss of ice crystals
aloft for a brief period early Monday morning, however BUFKIT
soundings are not in support of this. Left ptype a snow mention for
now, but will have to monitor model trends. Early in the work week
the upper level pattern transitions to meridional as a long wave
trough works its way across the CONUS. At the surface, high pressure
remains the dominate feature and cold air is expected to backdoor in
Tuesday and again on Wednesday. 925 temperatures drop into the teens
below zero celsius (maybe even into the 20s below zero depending on
the model) by Tuesday afternoon. The cold air is short lived however
as models show a broad upper level ridge and above normal
temperatures setting up in the out periods.
.AVIATION...(For the 00Z TAFS through 00Z Saturday Evening)
Issued at 527 PM CST Fri Feb 14 2020
Other than the potential for brief periods of MVFR vsbys due to
blowing snow across the far eastern part of the are this evening,
VFR conditions will prevail across the area tonight and through
the day Saturday.
Area Forecast Discussion
National Weather Service Buffalo NY
705 PM EST Fri Feb 14 2020
Light lake effect snow showers and flurries will redevelop tonight
east and northeast of Lake Erie and Lake Ontario. Any lake effect
will end late tonight with clearing skies across the entire region.
Temperatures will fall below zero over much of the area with
readings colder than 10 below east of Lake Ontario. After a cold
start on Saturday, a warming trend then develops Saturday afternoon
through Sunday. A weak front may produce a few snow showers Saturday
night into Sunday morning. Low pressure will then cross the Great
Lakes Tuesday, bringing warmer temperatures and mixed snow and rain
changing to rain. Cold air will follow this system into Thursday
bringing more lake effect snow showers.
.NEAR TERM /THROUGH SATURDAY/...
Lake clouds remain congested over central Lake Erie early this
evening. Hard to tell exactly what is going on underneath these
clouds as the KCLE overshooting this activity. Will assume
there is at least some light snow showers activity in this
area. As the low level flow backs south-southwest later this
evening, except to see a bit of an uptick to this activity. The
lastest HRRR and NAMNest are not supportive of any activity of
Lake Erie tonight, therefore confidence is low and will back
off a bit from the previous forecast and only suggest a coating
to perhaps an inch at best with the better chances of any lake
effect activity focused more toward Grand Island and the
Tonawandas, perhaps as far south of metro Buffalo.
Better potential for snow with longer fetch and even colder air
aloft will reside toward the east end of Lake Ontario. This
band should develop later this evening as the land breeze off
rapidly cooling land areas south of Lake Ontario enhances the
convergence. Nighttime microphysics loop showing a nice band of
lake clouds now enveloping eastern Wayne through much of Oswego
Similar setup to Lake Erie in terms of inversion height and as
all the lake convective layer is in the DGZ. Though not great,
various short term models have bit better handle on potential
for a lake band which adds confidence in seeing at least a few
inches of fluffy snow especially late evening through most of
the overnight toward far western shore of Oswego county, but
mostly toward western shore of Jefferson county northward into
the Thousand Island region. Isolated snow amounts over 4 inches
will occur, but mainly expect 2- 4 inch type amounts from
Watertown north to the St. Lawrence River valley.
Otherwise, temperatures tonight should tank quickly this evening as
any residual cloud cover will quickly dissolve. Went well under most
guidance for the interior sections just away from the lakeshores.
Continued to go for lows over interior North Country below 10 below.
Winds should be light enough to restrict wind chill issues. With the
developing sw winds aloft late tonight, could see temps rise slightly
After a chilly start on Saturday, expect benign weather with mostly
sunny skies most of the day and temps rebounding into the mid 20s
east of Lake Ontario and near 30 elsewhere. Mid clouds increase late
ahead of front that swings through here later Saturday night.
.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY NIGHT/...
A weakening upper level trough will cross the Great Lakes Saturday
night into Sunday, with its trough axis over the WNY area on Sunday
morning. Some snow showers will spread across the area as the trough
axis tracks east across the WNY area. Chance POPs from early to late
morning on Sunday for most for snow shower potential. As
temperatures warm through the morning, rain will mix in with some of
the remaining snow showers. The overall moisture content for the
area is lacking, and most showers should be light. Snow
accumulations on Sunday will be limited to a light coating for areas
that do have snow showers. Temperatures Saturday night will be in
the mid 20s to near 30for areas south of Lake Ontario, and in the
upper teens to low 20s for the North Country. Temperatures on Sunday
will be in the mid 30s to near 40, with temperatures in the low 30s
across the higher terrain east of Lake Ontario.
A weak cold front will drop southeast across the Eastern Great Lakes
later Sunday. There will be a chance of snow showers across the area
as the front passes Sunday night, but again, moisture available will
be limited and any snow that does fall should be light and limited
to a few tenths of an inch. Behind the passing cold front, an area
of high pressure will build into the Great Lakes and will center
just north of Lake Ontario by Monday morning. Temperatures on Sunday
night will be in the low to mid 20s south of Lake Ontario and in the
upper teens for the North Country.
With high pressure influencing the area on Monday, dry conditions
area expected across the region for most of the day. An area of low
pressure over the central Mississippi Valley will track toward the
Central Great lakes Monday afternoon into the evening. This will
result in chance POPs across the far western portion of the area by
early Monday evening, and slowly expand eastward through the evening
hours as a weak warm front associated with the area of low pressure
pushes northward. Weak cold air advection from the earlier passing
cold front will drop daytimes highs a few degrees from Sunday, with
temperatures in the low to mid 30s south of Lake Ontario and in the
the mid to upper 20s for the North Country.
Monday night, the area of low pressure will track northeast across
the Central Great Lakes and center near James Bay by around daybreak
on Tuesday. As this area of low pressure tracks closer to the
region, POPs will increase and expand eastward across the area.
Likely POPs are expected across most of the area after Midnight.
Most of the precipitation will start out as snow with temperatures
still cool enough to support snow as the dominant p-type. The
exception being far western NY where enough warm air advection may
bring temps up just enough to mix rain in. The far southwestern
portion of the area may only briefly be snow before changing over to
rain completely, this as warm air advection occuring in this area a
bit longer helps warm temps up a bit quicker. Snow fall through the
daybreak timeframe will generally be around an inch. Temperatures
Monday night will have an early low of the upper 20s to low 30s for
areas from Buffalo to the Northern Finger Lakes with the low to mid
20s for the North Country. Areas across the far southwestern portion
of the forecast area will only drop to the mid 30s. Temperatures
will slowly warm through the night from west to east with warm air
advection ahead of the approaching storm.
.LONG TERM /TUESDAY THROUGH FRIDAY/...
Potent upper level shortwave will support a strengthening area of
surface low pressure that will be tracking to the northeast
somewhere in the vicinity of the central Great Lakes as we open the
period Tuesday morning. Expect precipitation to be ongoing area
wide. Precip type will be a mix of rain and snow south of Lake
Ontario, with mainly snow across the North Country to start the day.
However, deep southerly flow will be pumping in warmer air across
Western and North Central NY, which will quickly change any mix over
to rain Tuesday morning south of Lake Ontario, with the changeover
to rain across the North Country occurring during the early to mid
afternoon as high temperatures climb into the low and mid 40s across
the majority of our forecast area, with upper 30s found across the
Tug Hill and western Dacks. In addition, potential for strong winds
is something that often has to be considered with storms (especially
deepening low pressure systems) that track northeastward off to our
west across the central Great Lakes into Ontario. This area of low
pressure will only be slowly strengthening as it passes by to our
west, however it does not look that strong at this time. To add, the
strongest winds (~55 to 60kt) are located in the warm sector ahead
of the cold front which will make it difficult for the stronger
winds aloft to mix down to the surface. That said, this will be
monitored going forward.
Main upper trough axis and attendant surface cold front will push
across the forecast area sometime Tuesday night. This will usher in
another shot of much colder air, changing any lingering
precipitation over to snow. Some accumulation will be possible with
the remaining synoptic moisture lagging on the back side of the low,
transitioning to upslope and lake-driven snows as 850mb temps drop
to the minus teens C for the second half of the night. It will be
much colder Tuesday night as lows drop into the single digits across
the North Country, with teens elsewhere.
An upper level shortwave will move through the area on Wednesday
bringing the chance of snow showers to much of the area, with some
northwest flow lake effect snow showers possible southeast of the
lakes. This will generally be the case Wednesday night through
Thursday also as spokes of shortwave energy traverse the area and
boundary layer flow remains generally out of the northwest. Expect
only localized minor snow accumulations due to the overall lack of
A strong area of sprawling high pressure will build across the upper
and mid Mississippi Valley Thursday night into Friday. The influence
of this large high will be felt across just about the entire eastern
half of the CONUS. This should provide dry conditions for the end of
the work week. Expect below average temperatures Wednesday and
Thursday, before moderating back to near normal seasonal levels by
.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
High pressure will return VFR flight conditions to the TAF region
for the majority of the remainder of the TAF cycle. The exception
will be northeast of both lakes later this evening and early
overnight closer to Lake Erie (BUF and IAG) and later tonight closer
KART to Lake Ontario (ART). For all these locations, at least a few
hours of MVFR ceilings and flurries of snow will be possible. If a
band of snow can persist at all, could see at least some IFR vsby,
though vsby this low should be pretty transient.
Saturday...Mainly VFR. Possible LLWS Saturday night.
Sunday...VFR to MVFR in scattered snow showers.
Monday night...MVFR/IFR within snow.
Tuesday...MVFR with snow becoming plain rain. Rain changes back
to snow Tuesday night.
Wednesday...MVFR with lake effect snow showers.
Northwest flow will continue to weaken as high pressure drifts
across the region. The surface high will move off the east coast
Saturday. SSW winds will increase in the wake of the departing high
Saturday, although the wind direction will keep the bulk of the
higher waves in Canadian waters. Southwest winds will increase
further Saturday night and Sunday as a weak front crosses the
eastern Great Lakes, bringing another round of Small Craft Advisory
conditions to Lakes Erie and Ontario.