textproduct: Cleveland

WHAT HAS CHANGED

No significant changes from the previous forecast package. A prolonged stretch of sub-zero wind chills appears likely beginning this Friday.

KEY MESSAGES

1) In addition to the dangerously-cold wind chills this morning, a prolonged period of sub- zero wind chills appears likely beginning this Friday.

2) A widespread snow will return across the area on Wednesday. For the most part, generally light amounts are expected, though totals may near Advisory levels across Northwest Pennsylvania.

3) We are continuing to monitor potential impacts across our area from a developing system across the southern CONUS this weekend.

DISCUSSION

KEY MESSAGE 1...

An arctic air mass is currently in place across the region this morning, with recent observations revealing widespread wind chills of -15 to -20 degrees F and ambient temperatures near zero. Although temperatures will improve slightly this afternoon, a persistent southwest wind of 10 to 15 mph will result in near-zero to slightly sub-zero wind chills into tonight as the arctic air mass largely remains in place. A brief relief to the cold will arrive on Wednesday as a clipper system moves east through the Great Lakes, ushering in temperatures near or even slightly above freezing Wednesday afternoon.

Looking ahead, a prolonged period of sub-zero wind chills appears likely towards the end of the week into early next week as a strong cold front moves through the area on Friday. At this point, the coldest wind chills appear to be late Friday into Saturday, with medium to medium-high confidence (50 to 70%) for values to drop below -15 degrees F. Sub-zero wind chills still appear likely into early next week, though the degree of cold begins to become a little more uncertain given the developing system across the southern CONUS.

KEY MESSAGE 2...

The next system to watch will be another clipper on Wednesday into Thursday, bringing another period of widespread snow from west to east across the area. Generally light totals of 1 to 2 inches are expected as temperatures quickly warm into the low to mid-30s by Wednesday afternoon. Will continue to monitor trends across Northwest Pennsylvania where more persistent colder air will be in place as snow totals may reach Advisory levels (around 4 inches).

KEY MESSAGE 3...

Finally, we are keeping an eye on a developing system across the southern CONUS this weekend and its potential impacts to our area. As of now, confidence for at least 2 inches of snow remains low (20% or less), though probabilities over the past few model cycles have trended slightly upwards. At this point, these highest probabilities are generally located east of the I-71 corridor.

AVIATION /06Z Tuesday THROUGH Saturday/

Mostly clear skies are observed areawide as high pressure has built in. MVFR lingers across the lakeshore of Northeast Ohio and Northwest Pennsylvania as a primary snow band continues over Lake Erie. Light snow may start to impact parts of the region late Tuesday night. West-southwest winds of 10-15 knots with gusts to 20-25 knots decrease by Tuesday night.

Outlook...Areawide light snow is expected on Wednesday, followed by lake effect snow impacting Northeast Ohio and Northwest Pennsylvania Wednesday night through Friday. Areawide light snow may occur on Saturday.

MARINE

The main marine weather concerns now through the end of the week will be rough conditions expected to continue in the open waters of Lake Erie where it is ice free with elevated winds and waves. We have allowed the Gale Warning to expire but winds will continue to be from the west-southwest 15 to 25 knots today into tonight. There is a Heavy Freezing Spray Warning for most of today for the central and eastern basin of Lake Erie. We are temporarily not going to issue Small Craft Advisories for the time being due to widespread ice coverage in our nearshore water. Another low pressure system will track across the Great Lakes region Wednesday into Thursday with winds increasing from the southwest 20 to 30 knots. Winds will approach Gales for a brief time late Wednesday. An Arctic High pressure system will build over the Great Lakes by this weekend with more northwesterly winds late week and also decreasing later this weekend. Periods of freezing spray will continue with considerable ice growth expected on the lake through the weekend. With the very cold temperatures now through this weekend, ice growth and expansion on Lake Erie is expected.

CLE WATCHES/WARNINGS/ADVISORIES

OH...Cold Weather Advisory until noon EST today for OHZ003-006>014- 017>023-027>033-036>038-047-089. PA...Cold Weather Advisory until noon EST today for PAZ001>003. MARINE...Heavy Freezing Spray Warning until 4 PM EST this afternoon for LEZ146>149-166>169.