317 
FXUS61 KCLE 281509
AFDCLE

Area Forecast Discussion
National Weather Service Cleveland OH
1009 AM EST Mon Jan 28 2019

.SYNOPSIS...
Low pressure will move east to southern lower Michigan and then
northeast through the lower Great Lakes today and early 
tonight. A trailing cold front will sweep east across the region
this evening and usher Arctic air into the region through 
Thursday. A trough from the low pressure will linger back over 
the local area through Tuesday night. High pressure will move 
east across the region Thursday and Thursday night. Another 
reinforcing high pressure will build east into the lower Great 
Lakes by Saturday and will bring a return mild southerly flow to
the area for the weekend.

&&

.NEAR TERM /THROUGH TUESDAY/...
Update...No changes other than to chance sw/rw to s/r.

Update to the update...
Fixed forecast for tonight with the timing with the cold front.
Slowed timing of the falling temperatures, as temperatures won't
start crashing until after sunset. As a result, there will be a
longer period of time with potential mixed precipitation/rain
and have reduced snow totals for parts of the forecast area as
it will be too warm for snow. 

Updated Discussion...
Latest observations show most of the snow in advance of the low
pressure system remains over Illinois. The precipitation will
continue to advance east with time this morning into the western
portions of the forecast area. Eventually, the precipitation
will spread east over the entire area today. Timing still
appears to be on track at this time. Clouds advanced east a bit
faster than in the forecast so updated to advance clouds further
east.

Original Discussion...

A look at the global northern hemispheric circulation is beginning 
to show signs that the Arctic air from the North Pole will begin to 
flow back toward Russia once again in a similar fashion as what 
occurred through December. This will aid in ejecting the cold air 
mass expected Tuesday and Wednesday east of the area fairly quickly. 
This upper level pattern change will support the possibility of 
stronger ridges building into North America as we head into the 
weekend. The North Atlantic and Arctic oscillations are indicating a 
change to a strong positive phase over the next couple weeks and 
perhaps a warming trend.

At any rate, low pressure moving east toward the area today will 
bring with it precipitation in the form of snow initially.
Pressure gradient will support increasing winds across the area from 
a southerly component and some warm air advection will take place to 
support a possible mix of rain and snow today into the evening. Will 
hold off on mentioning any freezing rain at this time even though 
department of transportation road sensors are reporting temperatures 
in the teens. Day shift will have to monitor for possible icing if 
the rain occurs. Otherwise, a general 1 to 3 inches of snow is 
expected across the area with the storm system. Some light lake 
effect snow continues at Erie at this time but wind flow is 
beginning to shift around to the southeast ahead of the low pressure 
system. This should continue to disrupt the snow band during the 
morning hours. Latest satellite shows clouds associated with the 
lake snow band over Erie, PA are beginning to spread out as the 
shift in the flow begins to interact with the band.

Cold front ushering in Arctic air will move through the local area 
this afternoon and evening. Temperatures will begin to fall behind 
the cold front and the plummet will continue tonight into Tuesday. 
Highs in the warm air advection flow today will top out in the 
middle to upper 30s. Following the frontal passage the cold air will 
drop temperatures into the teens overnight and will remain nearly 
steady in the teens Tuesday. Perhaps single digits could be reached 
late afternoon Tuesday in the western third of the forecast area. 
Then, it is all down hill as reinforcing Arctic air arrives Tuesday 
night.

The synoptic snow will transition into lake effect snow Tuesday for 
the extreme northeast snowbelt. Otherwise, snow threat will taper 
off for the rest of the forecast area Tuesday.

&&

.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY NIGHT/...
There increasing confidence in dangerously cold conditions from
Tuesday evening through Thursday afternoon. Therefore, a Wind 
Chill Watch has been issued for the entire forecast area for
wind chills below -25F and potentially as cold as -40F. A deep
trough will enter the Great Lakes region on Tuesday and continue
southeast to over the eastern Lakes by Wednesday. In this
trough, a closed 488 dm low will be centered just north of the
forecast area and will usher in extremely frigid temperatures 
into the region with an arctic surface high sliding southeast 
on the back side of the system for Wednesday night into Thursday.
Forecast guidance has been persistent over the last several 
days with 850 mb temperatures in the -25 to -30C range over the
area by Wednesday morning, which will translate to temperatures
below zero degrees Fahrenheit at the surface. Temperatures will
likely remain below zero Tuesday night through Thursday, and 
high temperatures across the area may not go above zero degrees 
on Wednesday for the first time since January 1994 in many 
locations. Low temperatures on Wednesday and Thursday morning 
will be the coldest temperatures the region has felt since 
February 2015 and could break daily records by several degrees. 
See more on this in the climate section below. A residual trough
of low pressure at the surface will keep strong winds over the 
area during this time period with winds 10 to 20 mph, gusting to
30 to 35 mph. This will translate to wind chills of 25 to 35 
degrees below zero, with some spots in northwest Ohio perhaps 
getting as as cold as 40 degrees below zero. This will allow for
life-threatening cold conditions with frostbite and hypothermia
possible in the matter of minutes.

Aside from the cold temperatures, the Great Lakes have the
potential to be active through the period, as arctic air over
the non-frozen portions of the lakes will provide moderate to
extreme instability to generate lake effect snow. As mentioned
in prior forecast discussions, not entirely sold on the extent 
of lake effect snow in our forecast area, as there are concerns 
with moisture in the boundary layer and the impact of strong 
winds, which may not allow for residence time over the lake for
good saturation and deep convective bands of snow. Plus, the
lake will be freezing up rapidly, which won't completely shut
down the lake effect, but it may diminish how much help the lake
will give. Finally, mean flow over the lake appears to be 
southwesterly for much of the period, which is more favorable 
for snow in end up in western New York, rather than NW PA or NE 
Ohio. With this, have maintained a 50-60 percent pop over Erie 
County PA quickly diminishing south and west. If lake effect
bands can build further south or mean flow shifts more westerly,
then Erie County PA could see more snow than currently
forecasted. Elsewhere, conditions should be dry until Thursday
night when a weak disturbance will enter the Ohio Valley and
give a chance for snow, but some uncertainty there.

&&

.LONG TERM /FRIDAY THROUGH SUNDAY/...
Still several differences in the long term forecast guidance to
be too confident in much at this point. However, the lone
exception is that the cold pattern appears to break as arctic 
high pressure will continue to the East and warm air advection 
will begin streaming into the region. Otherwise, the ECMWF
depicts a weak clipper system moving to the north of the area
for the weekend, while the GFS has a deepening low entering the
Great Lakes region on Sunday. For now, just have warming
temperatures and generic chance pops for the weekend.

&&

.AVIATION /12Z Monday THROUGH Friday/...
Low pressure will move east toward the local area today. The low
will spread some warm air into the region today causing the snow
to become mixed with rain in the central portions of the area. 
Ceilings and visibilities will be lowering as the precipitation 
occurs. Expecting mostly MVFR to brief IFR conditions moving 
west to east into the area. Snow accumulations about 1 to 3 
inches across the area. Winds will increase as well today in 
advance of the low pressure system.

OUTLOOK...Non-VFR Monday through Tuesday morning. More Non-VFR 
expected late Tuesday night and then mainly northeast snowbelt 
by Thursday. Possible non-VFR all areas Friday.

&&

.MARINE...
Low pressure approaching the Great Lakes region today will allow
for increasing winds on the Lake. As this low passes to the 
north of the Lake tonight strong southeast flow with shift to
the south and then southwest for Tuesday. Winds will be in the
15 to 20 knot range, but will be on the increase on Tuesday with
a residual trough of low pressure over the region. For now have,
winds to 30 knots in the forecast on Tuesday night through
Wednesday night, but it's not inconceivable to see a brief
period of gales on the lake. Regardless, would likely need a 
small craft advisory for ice free areas on Tuesday through
Thursday. High pressure building into the region on Thursday
will relax winds and waves over the Lake and give a reprieve in
hazardous marine conditions for Thursday night through Saturday
morning. 

Arctic air entering the region on Tuesday and remaining over
the Lake through Friday will allow over considerable ice growth
on the lake. There could be some difficulty with the stronger
winds, but as winds relax on Thursday and Friday, ice growth
will be more certain. In addition, frigid air along with strong
winds will pose a heavy freezing spray threat in ice free areas
and appropriate headlines will probably be needed later this
week.

&&

.CLIMATE...
Temperatures this week could approach or break record low
temperatures across northern Ohio and NW PA. Here are notable
low temperature records/statistics for area climate sites:

Coldest Temperatures on Record:
Cleveland, OH (CLE): -20F on January 19, 1994
Akron-Canton, OH (CAK): -25F on February 24, 2015
Erie, PA (ERI): -22F on January 19, 1994 & February 16, 2015
Mansfield, OH (MFD): -22F on January 19, 1994 & January 10, 1985
Toledo, OH (TOL): -20F on January 20, 1984
Youngstown, OH (YNG): -22F on January 19, 1994

Last Date with High Temperatures Below Zero:
Cleveland, OH (CLE): -3F on January 19, 1994
Akron-Canton, OH (CAK): -5F on January 19, 1994
Erie, PA (ERI): -4F on January 19, 1994
Mansfield, OH (MFD): -5F on January 19, 1994
Toledo, OH (TOL): -1F on January 19, 1994
Youngstown, OH (YNG): -6F on January 19, 1994

Note: Mansfield had a high of 0F on February 15, 2015.

Record Low Temperatures for January 29:
Cleveland, OH (CLE): -17F in 1873
Akron-Canton, OH (CAK): -13F in 1977
Erie, PA (ERI): -10F in 1977
Mansfield, OH (MFD): -14F in 1977
Toledo, OH (TOL): -9F in 1963
Youngstown, OH (YNG): -12F in 1977

Record Low Temperatures for January 30:
Cleveland, OH (CLE): -4F in 1873 
Akron-Canton, OH (CAK): -6F in 1965
Erie, PA (ERI): -4F in 1915
Mansfield, OH (MFD): -4F in 1934 and 1966
Toledo, OH (TOL): -5F in 1965
Youngstown, OH (YNG): -8F in 1965

Record Lowest High Temperatures for January 30: 
Cleveland, OH (CLE): 8F in 1977
Akron-Canton, OH (CAK): 7F in 1977
Erie, PA (ERI): 8F in 1977
Mansfield, OH (MFD): 4F in 1977
Toledo, OH (TOL): 8F in 1977
Youngstown, OH (YNG): 6F in 1977

Record Low Temperatures for January 31:
Cleveland, OH (CLE): -5F in 1948 and 1971
Akron-Canton, OH (CAK): -5F in 1948
Erie, PA (ERI): -6F in 1899
Mansfield, OH (MFD): -5F in 1971 and 2009
Toledo, OH (TOL): -5F in 1971
Youngstown, OH (YNG): -9F in 1948

Record Lowest High Temperatures for January 31:
Cleveland, OH (CLE): 5F in 1971
Akron-Canton, OH (CAK): 8F in 1971
Erie, PA (ERI): 6F in 1971
Mansfield, OH (MFD): 7F in 1971
Toledo, OH (TOL): 6F in 1971
Youngstown, OH (YNG): 5F in 1971

&&

.CLE WATCHES/WARNINGS/ADVISORIES...
OH...Wind Chill Watch from late Tuesday night through Thursday 
     afternoon for OHZ011>014-020>023-031>033-038-089.
     Wind Chill Watch from Tuesday evening through Thursday 
     afternoon for OHZ003-006>010-017>019-027>030-036-037-047.
PA...Wind Chill Watch from late Tuesday night through Thursday 
     afternoon for PAZ001>003.
MARINE...None.

&&

$$
SYNOPSIS...Lombardy
NEAR TERM...TK/Lombardy/Sefcovic
SHORT TERM...Sefcovic
LONG TERM...Sefcovic
AVIATION...Lombardy
MARINE...Sefcovic
CLIMATE...