textproduct: Cleveland

WHAT HAS CHANGED

Only minor changes to the forecast this cycle is to adjust temperatures this morning down a few degrees which could bring freezing fog impacts. Visibility was also adjusted based on current observations and trends as the Dense Fog Advisory remains in effect.

KEY MESSAGES

1) A Dense Fog Advisory continues as visibility less than a quarter of a mile is observed from the I-71 corridor, eastward. Conditions will begin to improve mid-morning.

2) Above average temperatures expected through Friday before falling near normal for the weekend. With the increased temperatures, the remaining snow pack will melt providing a minor risk in river rises and ice jams.

3) Periodic precipitation expected this week. Wednesday will have the highest potential for rain showers with another chance on Friday. Rain/snow mix possible this weekend with a colder air mass over the region.

DISCUSSION

KEY MESSAGE 1... Plenty of low level moisture remains across the region behind a departing low to the east in addition to light winds will has allowed for dense fog to form. Main areas of focus for visibilities less than a quarter mile will be east of the I-71 corridor, though there will be some pockets of decreased visibility to the west as well. The dense fog will persist through the mid-morning hours on Monday and may impact those commuting. The Dense Fog Advisory currently in effect runs until 11AM this morning. Temperatures will begin to rise with diurnal heating that will help dissipate the fog.

KEY MESSAGE 2... Above normal temperatures will continue through the majority of the forecast period due to west to southwesterly flow across the region. Most days will have high temperatures in the mid 40s to mid 50s with Wednesday being the exception. A warm front will pass through the area Wednesday morning that will increase the southerly flow and WAA allowing for temperatures to rise into the mid to upper 50s with some locations in central Ohio touching the low 60s. Temperatures across the northern portion of the CWA won't reach as high as the warm front will pass through later and precipitation will be moving in the region. Not anticipating any record high being broken on Wednesday as most locations will stay 5 to 10 degrees below those records. With the increased temperatures, the remaining snow pack will melt and may give a minor response in streams and rivers that will have their ice deteriorating as well. This may cause some localized ice jams in places if the response is great enough and will need to be monitored. Temperatures will fall back down around normal this weekend as a series of low pressure system move through the region.

KEY MESSAGE 3... A series of low pressure system will move through the region this week. Wednesday will have the greatest chance of precipitation this week as a low moves into the western Great Lakes pulling a warm front north through the region that morning. The low will stall out across Wisconsin which may limit the southern extent of the precipitation. Regardless, measurable rainfall is expected area wide. Current forecast has QPF totals of around 0.10" in the southern portion of the CWA, and up to around 0.50" in NE OH and NW PA. Can't rule out a rumble of thunder or two as there will be some weak CAPE of 200-500 J/kg. Additionally, with the approaching low, winds will begin increasing as the pressure gradient tightens and a strong LLJ moves overhead. Winds will be gusting around 25-35mph with the highest gusts in western Ohio.

Another chance for rain showers will on Thursday night into Friday as a low pressure system tracks to the northwest. Staying in the warm sector of the low will allow for all precipitation to fall as rain. For the weekend, there is some discrepancies in the models as to the development of the next system There will be CAA behind the low on Friday that will change over any lingering rain Friday night and Saturday morning to a rain/snow mix. With the colder temperatures this weekend, if any precipitation does occur, it will likely fall as a rain/snow mix or as wet snow.

AVIATION /06Z Monday THROUGH Friday/

Fog and low stratus have developed across the region and will continue to expand overnight. Many locations will fall to IFR and LIFR with dense fog expected at KCAK, KYNG, and KMFD. There is less certainty on the extent of LIFR conditions north and west for the remaining terminals. Fog and low stratus will be slow to mix out on Monday and may wait until better mixing with arriving high pressure in the 15-17z range. VFR conditions will then overtake the region with high pressure building in and light southwest winds will be favored. Some mid-level clouds will build in from the north, late in the TAF period.

Outlook...Non-VFR possible in rain Wednesday.

MARINE

Aside from some patchy fog on Lake Erie this morning, winds will be 12 knots or less today, increasing to southwesterly at 15-20 knots tonight. The next window of elevated winds comes on Wednesday as a warm front lifts north across Lake Erie and southerly winds increase to 15-25 knots. Areas of fog will be possible again. These elevated winds along with much above normal temperatures across the region this week will continue to rot the ice with ice floes expected. Shore ice may break off and any available shipping channels may be closed. It is important for people to stay off the ice this week or risk getting stranded.

The weather pattern looks active into this weekend and expect to see enhanced easterly winds ahead of a system on Thursday night, veering to westerly Friday night and northwesterly over the weekend.

CLE WATCHES/WARNINGS/ADVISORIES

OH...Dense Fog Advisory until 11 AM EST this morning for OHZ009>014- 017>023-027>033-036>038-047-089. PA...Dense Fog Advisory until 11 AM EST this morning for PAZ001>003. MARINE...None.