Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 01/05/18
Area Forecast Discussion
National Weather Service Hastings NE
543 PM CST Thu Jan 4 2018
.SHORT TERM...(This evening through Friday)
Issued at 323 PM CST Thu Jan 4 2018
Skies are mostly clear across the forecast area this afternoon. With
westerly winds, the temperatures have warmed up to near or above
freezing.
The main concern for tonight into Friday morning will be fog. With
some snow melt going on and the current dew points warmer than the
current forecast lows, there could be some fog around. On the flip
side, there will be some wind tonight, even if it is light, and it
should be from the north. Have decided to keep mention of some
patchy fog mainly in the west, but wonder if there may be some
further to the east as temperatures in the east rise to around
freezing as well. The fog will last for a while in the morning
before dissipating.
There will be a cold front that pushes into the area from the
northeast during the night. That will keep the temperatures on the
colder temperatures tonight. The colder temperatures will push into
the forecast area during the day on Friday. There will be an
increase in clouds as the colder air moves into the area.
.LONG TERM...(Friday night through Thursday)
Issued at 323 PM CST Thu Jan 4 2018
There are a few periods of interest during the period. First, will
be the warming trend for the weekend. After the cold on Friday,
there will be warm advection for Saturday and with some clearing,
the temperatures will warm a little. Temperatures continue to warm
on Sunday, but at the same time there is an upper level wave that
moves through the area and gives a chance for precipitation. The
models have had some differences from run to run and model to model
so there is some uncertainty, but there appears to be at least a
small chance for mainly the southeast part of the forecast area. The
problem with this is there will be some mixed precipitation. Have
decided to keep some sleet in the forecast, but with the trend
toward less precipitation will have to see how much there will be.
The warming trend continues Monday and Tuesday as well and
temperatures remain steady for Wednesday. Tuesday appears to be the
warmest day of the week.
The next period of interest will be Wednesday afternoon into
Thursday. There is an upper level low moving through the plains
during this time. A surface low and cold front move through, as
well. There have been a few differences in the models. The 12Z GFS
and the 00Z ECMWF were similar, but the 12Z run of the ECMWF is a
little slower. The Canadian is slower and weaker than either of
them. As it looks at this time, there could be some rain as early as
Wednesday afternoon for much of the forecast area, but the cold air
moves into the area later in the afternoon and continues to push
through during the evening. Most of the area will just have rain
changing to snow, but the far southeast could see a little sleet
during the transition to snow. With some of the model differences,
will have to keep an eye on this system as it approaches the area.
&&
.AVIATION...(For the 00Z KGRI/KEAR TAFS through 00Z Friday)
Issued at 528 PM CST Thu Jan 4 2018
Stratus currently across the Dakotas will sink into the area
after midnight tonight. The expectation is still that ceilings
may drop to IFR, but I have delayed the onset of the lowest
ceilings to near dawn tomorrow. This better matches the RAP model
guidance.
Winds will remain light and variable tonight, which when coupled
with moisture from the melted snow, may lead to some patchy fog as
well. Models remain variable on location, but the western edge of
the stratus deck is probably the most favorable, therefore I
believe Kearney stands a better chance to see reduced visibility.
IFR ceilings are expected to lift to MVFR by mid morning, but
stratus will likely hang around for most, if not all, of the
daylight hours on Friday.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...None.
KS...None.
&&
$$
SHORT TERM...JCB
LONG TERM...JCB
AVIATION...Mangels
Area Forecast Discussion
National Weather Service Grand Rapids MI
1025 PM EST Thu Jan 4 2018
LATEST UPDATE...
Update
.SYNOPSIS...
Issued at 330 PM EST Thu Jan 4 2018
We will remain bitter cold into the weekend. Wind chill readings
will become dangerously low tonight, ranging from 10 below zero near
the lake to 25 below zero well inland. Lake effect snows will
continue, especially west of U.S. 131, where another 3 to as much as
9 additional inches can be expected through Saturday.
All areas should see snow Sunday and Sunday night and again Thursday
of next week. Temperatures will finally warm next week, when most
daily highs should be in the 30s.
&&
.UPDATE...
Issued at 1023 PM EST Thu Jan 4 2018
The good radiational cooling inland has supported lower
temperatures. Some mesonet stations were already around -10
degrees in NW Kent County.
UPDATE Issued at 850 PM EST Thu Jan 4 2018
Skies have scattered out away from the lakeshore. This forecast
update reflects less in the way of cloud cover for these locations
for the rest of tonight. Temperatures were also lowered as less
cloud cover is expected.
The main band of snow remains west of Muskegon. The Latest ESRL
HRRR does bring some banding onshore later tonight around
Muskegon. Not sure if this will be the case given the colder
temperatures over the inland areas. For now will keep the headline
going. Where the band is onshore...impacts were occurring.
&&
.SHORT TERM...(This evening through Saturday)
Issued at 330 PM EST Thu Jan 4 2018
Little change expected through Saturday. Arctic air will remain in
place. Highs Friday and Saturday will be in the single digits inland
to around 15 toward Lake Michigan. Overnight lows will drop toward
minus 10 each night, but a bit warmer toward the lake where clouds
prevail. Winds will be fairly light, but still adding to the chill.
Will have a wind chill advisory for all areas except the lakeshore
counties. Wind chill readings of -15 to -25 will be commonplace
tonight. The far northern interior could even flirt with wind chill
warning criteria.
As far as the lake effect, it will continue into Saturday, before
finally diminishing Saturday afternoon. Mean low level wind remains
335-350 through the next 48 hours and the moisture remains deep
enough to expect little overall change. The headlines along the
coastal counties will continue. Generally expect 3 to 9 inches over
the next 48 hours in the headline region.
.LONG TERM...(Saturday night through Thursday)
Issued at 330 PM EST Thu Jan 4 2018
The main highlight of the long term period is that warmer
temperatures are finally expected.
We begin the temperature rebound on Sunday with southerly winds on
the back side of a departing sfc high, with high temperatures
reaching 25 to 30 degrees. On Monday it looks like most of the area
will reach or exceed freezing, then only a minor cool down occurs on
Tuesday before another warm up ensues for Wednesday into Thursday
when highs near 40 are not even out of the question. The polar jet
retreats during this time and a srn stream trough over the central
plains helps develop a downstream ridge over the Great Lakes Rgn.
It should be noted that there is still decent ensemble spread for
the mid to late part of next week in terms of how warm it may get,
but is certainly something to watch.
In terms of precipitation events, it still looks like some light
snow can be expected in the warm advection pattern on Sunday into
early Monday, then perhaps some scattered snow (or rain?) showers
toward the mid to late part of next week as developing srn stream
system starts sending some moisture our way.
&&
.AVIATION...(For the 00Z TAFS through 00Z Friday evening)
Issued at 623 PM EST Thu Jan 4 2018
Generally looking at VFR weather at the TAF sites tonight. Band of
snow just west of KMKG is forecasted to move slowly east and break
up somewhat. Based on that...I do feature some snow for that TAF
site later this evening. Clouds may redevelop during the afternoon
inland. Thus I featured afternoon MVFR for KLAN and KJXN.
&&
.MARINE...
Issued at 330 PM EST Thu Jan 4 2018
Brisk NNW winds continue around 25 knots and the small craft
advisory will be maintained.
&&
.HYDROLOGY...
Issued at 330 PM EST Thu Jan 4 2018
The advisory continues at Evart. However, we have coordinated with
the Evart Police Department and Public Works about river conditions.
For now, there is no immediate threat with no impacts being
observed/reported.
Despite some erratic behavior on a few other gauges, readings are
purely ice affected. Overall, levels are below action stage and seem
to be fairly stable. The question lies in next week`s temperature
transition. Yesterday it seemed that we would approach or slightly
top freezing. Members in some of the latest guidance are well into
the 40s. The cooler solutions are in the upper teens. Generally
speaking, when solid river ice forms, free movement can occur with a
couple of days (or more) near 50 degrees.
There is some confidence in milder weather, but the extent of the
warmth is still uncertain. If temperatures trend warmer in guidance,
we may need to keep an eye on river levels next week.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...Winter Storm Warning until 7 AM EST Saturday for MIZ064-071.
Wind Chill Advisory until 11 AM EST Friday for MIZ038>040-
044>046-051-052-057>059-065>067-072>074.
Winter Weather Advisory until 7 AM EST Saturday for MIZ037-043-
050-056.
LM...Small Craft Advisory until 10 AM EST Saturday for LMZ844>849.
&&
$$
UPDATE...MJS
SYNOPSIS...JK
SHORT TERM...JK
LONG TERM...Meade
AVIATION...MJS
HYDROLOGY...JAM
MARINE...JK
Area Forecast Discussion
National Weather Service Blacksburg VA
921 PM EST Thu Jan 4 2018
.SYNOPSIS...
Strong Arctic high pressure will gradually build in from the
northwest tonight through Saturday resulting in continued
bitterly cold temperatures and low wind chills. The center of
the high should pass overhead by the end of the weekend ahead of
the next complex area of low pressure that arrives for early
next week.
&&
.NEAR TERM /THROUGH FRIDAY/...
As of 915 PM EST Thursday...
No changes were made in time or location to the current wind
chill advisories/warnings. Over the past 1-2 hours, an uptick in
wind gusts has been observed as another vort lobe swings through
our area as seen on GOES-east. The HRRR low level wind forecast
has a good handle on this trend and indicates low level winds
peak around 06Z, and it is not until after 10-12Z before wind
begin to diminish. Pushed up wind gusts a few MPH in the
forecast update and lowered temps a degree or so.
Bands of light snow continue to bleed into the foothills of VA,
and expanded low POPs east to cover these areas including
Carroll, Floyd and Franklin counties. High-res model soundings
show depth of shallow moisture layer not diminishing until
Friday morning. While this will fall for several hours, the
very high snow-liquid ratio will keep accumulations light.
Expect both snow showers and winds to decrease some Friday
morning as the low level flow briefly turns more westerly and
forecast soundings show the depth of moisture decreasing from
above as the inversion lowers. However still enough to keep some
flurries/snow showers going just from the cold advection so
keeping in clouds/pops west and mainly clear east.
Better subsidence along with even drier air will work in during
Friday with lingering snow showers likely early across the west
before shrinking in coverage from south to north by afternoon.
Winds should still be gusty but not quite as strong as today
with the pressure gradient slowly weakening as low pressure
pulls farther away. However still cold enough for advisory level
wind chills to linger until midday and perhaps all day across
the mountains espcly where clouds linger. Otherwise despite more
insolation, little change in 85h temps suggests highs mostly
teens west to around 20 Blue Ridge, and mid/upper 20s east
where slight downslope warming should help a bit given the dry
air.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY NIGHT/...
As of 215 PM EST Thursday...
Very cold with gusty winds and dangerous wind chills into the weekend,
some moderation Sunday.
Arctic high pressure will continue building down from the upper midwest
and will bring the core of the cold air through the region Friday night
and Saturday. Winds will also remain blustery and create very low wind
chill values through Saturday morning. Lingering upslope snow
showers/flurries will also continue west of the Blue Ridge with some
light additional accumulation possible mainly at the higher elevations
around western Greenbrier county WV.
As the center of the high drifts over the region Saturday night
conditions, winds will slacken and there should be a window of time
with good conditions for radiational cooling before mid/high clouds
move in and winds shift to the southeast late. If clouds are slower to
move in and a strong enough surface inversion can become established to
keep winds at bay, temperatures could really plummet to some
impressively cold lows by daybreak Sunday.
As the high moves off to our east on Sunday and winds become southerly
we will finally start to break out of the cold. The persistent upper
low that has been keeping the cold air locked in over the eastern US
will give way to a much more progressive and warmer pattern. A very
brisk southwesterly low level jet will start advecting warmer air in
the region, and good isentropic lift will develop Sunday night ahead of
a frontal system approaching from the west as the region gets split by
low pressure moving by well to our north and south. Low level moisture
return will be slow so it looks like the better chances for
precipitation will be holding off until mainly after daybreak Monday.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
As of 215 PM EST Thursday...
Definitely trending to a warmer synoptic pattern next week as
progressive low amplitude flow evolves to a deepening trof in the west
with sympathetic ridging in the east. Expect temperatures to be at or
slightly above normal by midweek.
Cold front will be moving through the region Monday/Monday night with a
good chance of precipitation. With all of the warming aloft and cold
air at the surface Bufkit soundings have a distinct look of freezing
rain, especially given the very cold ground temperatures coming off our
spell of cold weather. The combination of QPF and cold temperatures
looks favorable for a decent glaze of black ice Monday before surfaces
go above freezing. Will continue to assess potential impacts with later
model runs.
As this system pulls away on Tuesday we can expect some lingering
upslope rain/snow showers west of the Blue Ridge, followed by generally
dry weather through midweek.
&&
.AVIATION /02Z FRIDAY THROUGH TUESDAY/...
As of 635 PM EST Thursday...
A strong storm system off the New England coast this evening
will continue to move away from our area, but strong northwest
winds in the wake of the system will keep persistent MVFR cigs
to mountain TAF sites including KBCB, KBLF, and KLWB through at
least Friday morning. Ceiling may drop to IFR levels at KLWB and
KBLF tonight with localized snow showers.
East of the Blue Ridge (KROA/KLYH/KDAN), VFR conditions should
continue with ceilings at ROA remaining at VFR levels.
Very strong northwest winds will continue to create issues with
flying through Friday morning with gusts to 40+ knots possible
over the mountains, and 30+ knots possible across the Piedmont
locations.
Of note...the observation from KDAN is unavailable due to
problems with power from early this morning. Will continue to
provide a forecast TAF without a NIL AMD since VFR and winds
remain the only issue at this point.
Extended Discussion...
A prolonged period of strong northwesterly winds with MVFR to
flight restrictions due to upsloping clouds and snow showers
will persist west of the Blue Ridge into Friday night/early
Saturday East of the Blue Ridge, gusty downsloping winds will
maintain VFR flight conditions across the Piedmont.
Arrival of the surface high pressure system on/by Sunday will
bring diminishing winds, a return to widespread VFR weather
(even in the mountains), and slowly moderating temperatures.
Arrival of a fast moving low pressure system may result in
another round of sub-VFR flight restrictions mainly west of the
Blue Ridge on Sunday night - spreading east across the Piedmont
on Monday. Widespread MVFR to IFR restrictions with a wintry mix
of precipitation gradually transitioning over to rain is
expected as the system moves northeast through the region on
Monday. Return to VFR across the region should occur on Tuesday
with perhaps only some lingering MVFR cigs across the mountains
early on.
&&
.FIRE WEATHER...
Antecedent conditions are dry. In spite of the cold, the
dryness of the current Arctic airmass and lack of meaningful
precipitation the last 30-60 days is beginning to set the stage
for potential fire concerns. Sun angle is low so the active burn
window is small, however with little or no moisture recovery at
night conditions are becoming favorable to sustain fire starts
if they occur. Ignition sources for this time of year given the
cold weather would most likely come from hot ashes being dumped
out by folks using wood stoves.
&&
.CLIMATE...
A continued series of Arctic air masses is expected during the
next 3 or 4 days, likely threatening record low maximum
temperatures and perhaps even record low minimum temperatures.
Here are the records for the next several days.
Climate Records Summary
Thursday 01/04/2018
Site LoMax Year
KBLF 17 2010
KDAN 26 1979
KLYH 22 1919
KROA 24 1919
KRNK 19 1979
Friday 01/05/2018
Site MinT Year LoMax Year
KBLF -4 1981 14 1999
KDAN 9 1958 25 1981
KLYH 1 1969 21 1959
KROA 5 1969 16 1912
KRNK -2 1981 12 1981
Saturday 01/06/2018
Site MinT Year LoMax Year
KBLF -4 2014 14 1988
KDAN 10 1999 27 1999
KLYH 3 1924 18 1912
KROA 2 1924 18 1912
KRNK -2 2014 13 1959
&&
.EQUIPMENT...
As of 400 AM EST Thursday...
Several stream and river gages have been reporting bad data, and
is due to ice affecting the gage. Most of these have been
deactivated on our web page. Given the dry conditions, the
threat of flooding is zero.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...Wind Chill Advisory until noon EST Friday for VAZ007-009>019-
022>024-035.
Wind Chill Warning until noon EST Friday for VAZ020.
Wind Chill Watch from Friday afternoon through Saturday
morning for VAZ020.
Wind Chill Advisory until 10 AM EST Friday for VAZ032>034-
043>047-058-059.
NC...Wind Chill Advisory until noon EST Friday for NCZ001-002-018.
Wind Chill Advisory until 10 AM EST Friday for NCZ003>006-019-
020.
WV...Wind Chill Advisory until noon EST Friday for WVZ042>044-507.
Wind Chill Warning until noon EST Friday for WVZ508.
Wind Chill Watch from Friday afternoon through Saturday
morning for WVZ508.
&&
$$
SYNOPSIS...JH/WP
NEAR TERM...JH/PH
SHORT TERM...MBS
LONG TERM...MBS
AVIATION...JH/PH
FIRE WEATHER...PM
CLIMATE...RAB/WP
EQUIPMENT...WP