NWS Cleveland, OH wrote its last area forecast discussion before the first event at Feb 15, 4:54 AM EST, 2 hours 6 minutes earlier.
Area forecast discussion, Feb 15, 4:54 AM EST, 2 hours 6 minutes before
Area Forecast Discussion
National Weather Service Cleveland OH
454 AM EST Mon Feb 15 2021
.SYNOPSIS...
Low pressure developing over the northern Gulf Coast will move
northeast today and tonight, reaching the Upper Ohio Valley by
daybreak on Tuesday. This system will continue northeast on
Tuesday and high pressure will build in from the northwest on
Tuesday night into Wednesday. Another northern Gulf Coast low
will form on Wednesday night and move northeast into the Ohio
Valley by Thursday night.
&&
.NEAR TERM /THROUGH TUESDAY/...
The Winter Storm Warning remains in place for the forecast area
through 1 PM on Tuesday with snow totals generally ranging from
8 to 12 inches with slightly less southeast with some potential
mixed precipitation. Snow will spread across the region this
morning with a quick 1 to 2 inches, lessen this afternoon, and
then return this evening with high intensity. The heaviest snow
totals now appears to be focused into portions of Northwest and
North Central Ohio and this is where snow amounts greater than a
foot are possible. Some mixed precipitation may enter our
southeast counties this evening and diminish some of the snow
totals there with some light icing possible. Residual snow will
linger across areas closer to the lake/into the snow belt on
Tuesday with an additional inch or two before the system fully
departs.
The synoptic setup for this event remains fairly similar to
previous forecasts. This morning a trough is situated over the
central Appalachians and to the northwest, low level
frontogenesis, isentropic lift, and the right entrance region of
an upper level jet are allowing for snow to enter the forecast
area. The snow is morning is honestly a bit less impressive
than previously expected as this band of snow has needed to
fight off drier air and began as virga before starting to reach
the surface over the last couple of hours. This feature will
continue east and snow will overspread the region this morning.
At this point, thinking accumulations will be more in the range
of 1 to 2 inches with this morning's snow. However, cameras
over NW Ohio, including Toledo and Findlay show that the snow
will stick to untreated roadways and bridges and this morning's
commute could be messy in some areas. As the upper level jet
exits to the northeast, snow should taper across the area this
afternoon and either cut off completely or be very light.
The focus then turns to the main event tonight. A shortwave
trough will support the development of low pressure along the
northern Gulf Coast today and bring this low northeast to the
upper Ohio Valley tonight. The setup continues to favor heavy
snowfall development across the region tonight as southerly flow
level flow will usher Gulf moisture into the region. In
addition, this flow will bring warmer air in the form of a
TROWAL centered around 700 mb and an impressive baroclinic zone
across the heart of the forecast area. Finally, the region will
find itself under the left exit region of a 130 kt upper level
jet. As the low pressure system moves northeast, these
components will come together to allow for heavy snow across the
region and where these features align the best, there will be a
deformation zone with mesobanding, allowing for even higher
snowfall totals. At this time, this seems to be somewhere in
Northwest to North Central Ohio overnight. In addition, while
Lake Erie is frozen over, northeast flow off the lake could
allow for some light lake enhancement of the synoptic snow, but
this is minor compared to other features. In the end, believe
that 6 to 12 inches of snow falls across the area tonight with
those higher amounts out west. Northerly winds with temperatures
in the teens will allow for winds chills in the single digits to
near zero tonight.
There are two newer challenges to the forecast this morning that
were considered. First, there is some question to when the heavy
snow enters this evening. Conditions will rapidly change over
the course of the evening commute. Heavy snow will probably be
on the southwest periphery of the forecast area at 4 pm, but the
temperature gradient tightens quickly after this time as the mid
level vort max pivots in from the southwest and suspect that
snow will be widespread by 7pm. So any travel should be
completed early this evening, if at all needed. The other
forecast change was to address how much warm air would enter
aloft this evening and would have hamper snow across the region
this evening. Trends in the overall guidance show the low
pressure center getting close to Pittsburgh, rather than farther
southeast, and this would bring the warm nose with temperatures
above freezing aloft into our far southeast forecast area,
namely Knox to Mahoning/Trumbull Counties. Therefore, have
introduced some wintry mix to the forecast and cut down slightly
on snowfall totals. There remains some uncertainty on the end
forecast solution in this region, but this will likely not
change overall impacts.
The low departs to the northeast on Tuesday and residual low
level moisture and flow off Lake Erie will allow for lingering
snow showers across the northern forecast area before tapering
off considerably by afternoon. Another 1 to 2 inches are
possible, mostly in the snow belt. Highs on Tuesday will be
around 20, plus or minus a couple of degrees.
&&
.SHORT TERM /TUESDAY NIGHT THROUGH FRIDAY/...
The low pressure that will impact the area during the near term
forecast period will continue to track northeast and off the coast
of Maine Tuesday night. As a result, winds will become northwesterly
into Wednesday morning, allowing for below normal low temperatures
to spread across the area Tuesday overnight. With this set up and
portions of the eastern basin of Lake Erie still unfrozen, have
opted to keep chance PoPs in for the primary snowbelt areas through
early Wednesday morning. Based on current guidance, these lake
enhanced snow showers are expected to produce little to no
accumulation. Overnight temperatures on Tuesday will be in the
single digits, approaching 0 in some locations. Wind chill
temperatures will remain a concern as much of the area is expected
to drop into the negatives.
On Wednesday, high pressure will briefly build across the area,
allowing for a brief break in wintry precipitation for much of the
day. Temperatures will continue to remain below normal with highs
reaching into the upper teens to low 20s. By Wednesday night, the
very active weather pattern continues as the area begins to receive
impacts from the next low pressure. This system is eerily similar to
the one going to impact the area in the next couple days. It will be
associated with a digging upper level trough across the central
United States which will aid in developing and deepening a low
pressure at the surface that is expected to develop along the Gulf
Coast and track northeast into the Ohio River Valley.
This evolution of this system has become more consistent amongst
models, suggesting a low pressure track to the southeast of the
area. Discrepancies exist with how far to the southeast the center
of the low go, however all models at this point keep us on the cold
side of the low. With this being the case, have opted to make snow
showers the primary weather type, although some mixed precipitation
cannot be ruled out for the far southeastern portion of the CWA.
That area in particular will need to be closely monitored in the
coming days. Impact from this system will persist through the day on
Friday with PoPs diminishing from west to east.
High temperatures on Thursday and Friday should be in the 20s,
possibly trending slightly colder in upcoming model runs. Wind chill
values will likely drop into the single digits, especially on
Friday, as winds increase to 10 to 15 knots from the west. Overnight
lows on Thursday will be near 20, again with wind chills in the
single digits.
&&
.LONG TERM /FRIDAY NIGHT THROUGH SUNDAY/...
High pressure will begin to build north across the Ohio River Valley
as the departing low moves off the East Coast. Winds are expected to
shift and become westerly into early Saturday morning. With this
winds, lingering moisture, and the projected fetch across Lake Erie,
have opted to keep snow showers in the forecast into Saturday
morning for the primary snowbelt areas. The biggest forecast
challenge for this potential lake enhanced snow is discerning how
much ice will form on the Lake throughout this week. If more of the
eastern basin become ice covered, then the chances of snow will
diminish.
The next system to keep an eye on will begin to develop over the
Midwest and track northeast through the Great Lakes region Sunday
into the beginning of next week. Current model runs keep northern
Ohio and NW PA in the warm sector, suggesting this could be more of
a liquid precipitation event, however this is still really far out
to confidently say. Throughout the long term period, high
temperatures will gradually warm to near normal with low
temperatures also gradually increasing over the weekend.
&&
.AVIATION /06Z Monday THROUGH Friday/...
The aviation forecast can only be described as it's all downhill
from here. Conditions across the area are starting at VFR or
MVFR and will trend down this morning as snow enters from the
west and south and will overspread the region by 12z this
morning. This snow will bring MVFR to IFR conditions, if not
lower through the airspace this morning. There appears to be a
very brief lull that may allow for a period without snow this
afternoon but low ceilings should still remain across the
region. The main snow show is tonight as snow reenters and
expecting a quick drop to heavy snow with IFR/LIFR conditions
across the area. The one item that isn't reflected in the TAFs,
specifically at KYNG, is that there is a chance for snow to
change over to either sleet or freezing rain around the end of
the TAF period into early Tuesday morning. Will need to monitor
precipitation type over eastern Ohio as slightly warmer air is
trying to creep into the region, making snow perhaps a bit less
clear cut for KYNG. Winds through the period will be northerly
at 12 knots or less.
Outlook...Non-VFR likely with periods of widespread snow late Monday
night through Tuesday night. Additional non-VFR with periods of
widespread snow are possible Wednesday night through Friday.
Some rain may mix with the snow briefly on Thursday.
&&
.MARINE...
Winds will gradually increase out of the northeast from 10 to 15
knots today to 15 to 25 knots overnight on Tuesday as a strong low
pressure system approaches the region from the southwest. Although
winds will be gusty across Lake Erie, they should remain below
Gales. No small craft advisory will be issued due to the nearshore
zones being primarily ice covered, however in areas where the ice is
broken apart, these winds will be hazardous to any small craft.
By Tuesday afternoon, the aforementioned low pressure system will
move off the coast of Maine, allowing for winds to shift to
northwesterly and weaken to 10 to 15 knots and persist through much
of the day on Wednesday. By Wednesday night, winds will shift to
become northeasterly again as another strong low pressure system
approach the Ohio River Valley from the southwest. Winds are
expected to intensify to 15 to 25 knots overnight on Wednesday and
persist into Friday night. Following a similar pattern as the
aforementioned low pressure, this one will move off the East Coast,
shifting winds to the northwest across Lake Erie and weakening them
to 10 to 15 knots.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...Winter Storm Warning until 1 PM EST Tuesday for OHZ003-006>014-
017>023-027>033-036>038-047-089.
PA...Winter Storm Warning from 7 AM this morning to 1 PM EST
Tuesday for PAZ001>003.
MARINE...None.
&&
SYNOPSIS...Sefcovic
NEAR TERM...Sefcovic
SHORT TERM...Campbell
LONG TERM...Campbell
AVIATION...Sefcovic
MARINE...Campbell