462 
FXUS61 KCLE 190607
AFDCLE

Area Forecast Discussion
National Weather Service Cleveland OH
107 AM EST Sat Jan 19 2019

.SYNOPSIS...
Weak high pressure over the region this evening will drift east
overnight as low pressure over the Southern Plains moves to the
central Mississippi Valley by morning. The low pressure area
will track to eastern Kentucky by Saturday evening and spread
significant snowfall to much of the area. The low pressure area
will move to New Jersey by Sunday morning as arctic high
pressure begins to build into the region in the wake of the
storm.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
Snow is quickly spreading east this evening. Light snow is being
observed in surface observations over southern lower Michigan. 
I will increase the timing of the snow slightly over northwest 
Ohio by a few hours. The snow is light with visibilites ~ 
2 miles so accumulations late this evening if any will be 
light. The moderate snow is still well to the west and will 
arrive in northwest Ohio near day break. I will also make a few 
adjustments to the hourly temperatures to reflect current 
trends. The rest of the forecast appears to be on track.

Previous Discussion...
Fairly quiet conditions are expected this evening as high 
pressure drifts east of the region. Then our attention shifts to
the developing storm system now over the Southern Plains. A 
dual jet structure has developed over the country with two areas
of upper vertical motion. The entrance region of the Quebec jet
will spread a streak of snow from TOL to nw PA by morning. 
Perhaps an inch can fall near TOL. Meanwhile the southern stream
jet will progress east with its attendant surface low.

Dual Jet structure will remain over the eastern states on 
Saturday and enhance cyclogenesis over the Ohio Valley. 
Isentropic lift associated with this storm will spread snow 
across the region Saturday morning. Only snow is expected as the
thermal profiles remain below freezing through the column.The 
snowfall will intensify and become moderate to heavy from about 
noon into the evening. Naturally the various model solutions 
offer a range of QPF with the general trend of less snow in the 
northwest Ohio with about 5" near TOL with the max along and 
north of US Route 30 east of MFD of about 8-10". NW PA will have
a bit more with 10-11".

The snow will taper off from west to east in the evening. As 
the storm approaches Saturday...the pressure gradient will 
increase and increase winds across the region from west to east 
from late morning into the afternoon. BUFKIT shows the mixing 
height reaching to levels to tap into the 40-45 knot winds aloft
so we can expected high wind gusts to mix down especially west 
of I-71 in the open farmland.

High temperatures will be just below freezing. Temperatures will
plunge into the teens Saturday night.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM SUNDAY/...
The main storm system will be pulling away from the region 
Sunday morning. There will be lingering light snow over eastern 
Ohio, secondary and primary Snowbelt areas Sunday morning. 
Arctic air will spill in during the day on Sunday with slowly 
falling temperatures. 850 mb temperatures will fall between -20C
to -25C Sunday afternoon and Sunday night. Temperature will 
fall through the teens on Sunday to the single digits Sunday 
night and Monday morning. Wind chills will fall to -10F to -20F.
A Wind Chill Advisory will likely be needed later this weekend.

Confidence low to medium on the Lake Effect potential because of the 
dryness of the Arctic airmass. High res and model range guidance 
show a northerly to north-northwest wind coming off Lake Huron 
across the western/central portions of Lake Erie Sunday afternoon 
through Monday. We will mention at least Lake Effect Snow Showers 
are likely for secondary and primary Snowbelt areas with the 
potential for a moderate to heavier snow band to form somewhere near 
the Cleveland area into northeast Ohio and the higher terrain areas. 
Several additional 3 to 6 inches of Lake Effect Snow is likely. 
There is low confidence of 6 inches plus in the Snowbelt but yet to 
be TBD.  Lake Effect snow showers continue into Monday with a 
decrease in snow showers Monday night. Temperatures start to rebound 
by Tuesday as the Arctic airmass shifts eastward.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
A sharp negatively tilted trough will swing through middle of next 
week with another cold front. Precipitation will be likely for the 
mid week system with rain, snow, or a rain/snow mix. Confidence and 
details are limited at this time. Models hint at another stronger 
storm system possibly affecting the region and East Coast by the end 
of next week with more snow and wind.

&&

.AVIATION /06Z Saturday THROUGH Wednesday/...
Widespread snow event to impact all terminals, with light snow
already falling at TOL, increasing in NW Ohio around 14Z, 15Z 
in Cleveland, and 17Z in NW PA. MVFR ceilings will remain VFR 
until snow develops followed by several hours of IFR and 1/2 
mile visibilites in falling and blowing snow. Northeast winds
will increase through the day on Saturday with gusts to 30
knots at several terminals during the late afternoon and
evening. Winds will back to more northerly on Saturday night. 
Periods of heavy snow are possible and will be most likely 
between 1 and 8 PM, especially at MFD/CAK/YNG. Conditions will 
begin to improve at the western terminals by 00Z but some 
blowing snow may continue beyond that time.

OUTLOOK...Non-VFR in snow at times across the snowbelt on
Sunday and Monday. Non-VFR possible Wednesday. 

&&

.MARINE...
Conditions will go down hill on the lake later tonight and during 
the day on Saturday. Small Craft Advisory is in effect for Saturday 
morning through Sunday evening. Winds will increase from the 
northeast to the north 20 to 30 knots with gusts over 35 knots 
likely. Waves will increase to 5 to 10 feet Saturday through Sunday. 
Arctic air will move in over the weekend with freezing spray likely 
given the very cold air, unfrozen lake, and strong gusty winds. 
Winds will start to relax by Monday and become variable. Southerly 
winds will return over the lake 15 to 25 knots middle of next week.

&&

.CLE WATCHES/WARNINGS/ADVISORIES...
OH...Winter Storm Warning until 4 AM EST Monday for OHZ010>014-
     020>023-089.
     Winter Storm Warning until 10 AM EST Sunday for OHZ009-017>019-
     027>033-036>038-047.
     Winter Storm Warning until 4 AM EST Sunday for OHZ003-006>008.
     Coastal Flood Watch from 7 AM EST this morning through Sunday 
     morning for OHZ003-007-009.
PA...Winter Storm Warning until 4 AM EST Monday for PAZ001>003.
MARINE...Small Craft Advisory until 7 PM EST Sunday for LEZ142>149.

&&

$$
SYNOPSIS...LaPlante
NEAR TERM...Garnet/LaPlante
SHORT TERM...Griffin
LONG TERM...Griffin
AVIATION...KEC
MARINE...Griffin