textproduct: Cleveland

WHAT HAS CHANGED

A Heat Advisory has been issued for the Ohio counties as heat indices will reach above 100 degrees starting Monday.

KEY MESSAGES

1) Hot and humid conditions are expected across the region this week.

2) Low chances for showers and thunderstorms today and tomorrow, then again on Friday as the surface high pressure breaks down.

DISCUSSION

KEY MESSAGE 1... High pressure will begin to build to the southeast as upper level ridging moves into the eastern half of CONUS. Concurrently, a low pressure system will move north across the Great Plains dragging a warm front through the region during the day tomorrow. This will bring much warmer and humid air in from the west-southwest and temperatures will begin to rise well above average starting tomorrow. The warm front will only clear the western counties in Ohio by tomorrow evening, and heat indices will rise as a result and exceed 100 degrees. A Heat Advisory has been issued for the I-75 corridor starting noon tomorrow. Hot and humid conditions will spread to the remainder of the area as the warm front pushes north Monday evening. An additional Heat Advisory has been issued for the rest of Northern Ohio starting at noon on Tuesday to account for this increased temperatures and heat indices. Both Heat Advisories will run through Thursday evening, though hot and humid conditions may last into the weekend with lower confidence. Heat indices will be the highest Wednesday and Thursday as they approach 105, with areas out west potentially eclipsing that mark. An upgrade to an Extreme Heat Warning may be needed for at least the I-75 corridor during that time period. To go along with the daytime heat, overnight lows will be warm as well. Temperatures will only drop down into the mid to upper 70s this week, providing little relief to to the heat. As mentioned above, confidence in heat related headlines decreases with the high pressure breaking down into the weekend.

KEY MESSAGE 2... Showers and thunderstorms are possible this afternoon along a stationary boundary that is located across the Ohio Valley. The best chance for any showers would be in eastern Ohio as the drift northward. Additionally, showers and possible in Northeastern Ohio and Northwestern Pennsylvania as well with interaction with the lake breeze. The boundary will move to the south this evening and precipitation chances will decrease. Tomorrow, as the warm front pushes north, there is a low chance for showers and thunderstorms across Northeastern Ohio and Northwestern Pennsylvania in the late evening to early morning on Tuesday.

Late in the week the upper level ridge will begin to break down and the surface high will weaken. A few long range models depict a shortwave moving through the region on Friday that could bring showers and thunderstorms back to the area. Will need to monitor how this unfolds throughout the week as there could be potential for organized thunderstorms.

AVIATION /18Z Sunday THROUGH Friday/

Widespread VFR conditions will diminish for many terminals tonight to MVFR and possible IFR and clearing skies, low level moisture, and weak winds result in patchy fog developing. Most terminals will reach these diminished conditions gradually beginning at 06Z Monday and peaking near 10Z. The only terminals likely not impacted by these diminished conditions will be KERI and KTOL, although confidence in diminish visibilities at KFDY remains low so opted to use TEMPO for 4SM but will have to monitor fog development. Any diminished visibilities should improve after sunrise tomorrow, eventually all returning to VFR by mid to late morning. Winds overnight will be light and variable before become sustained from the southwest at 5-10 knots. A lake breeze is expected to develop and possibly impact KCLE and KERI Monday afternoon.

Outlook...Mainly VFR conditions expected to persist as high pressure influences the area.

MARINE

High pressure will persist over the area into Monday before a warm front begins to lift north across the basin. Light northeast winds this evening will gradually veer to become south-southwesterly at 5-10 knots Monday night. Once the warm front fully lifts north, high pressure will build over the eastern US and persist into at least Friday. Southwest winds of 5-10 knots will be maintained through that period.

CLIMATE

Hotter and more humid weather is expected this Monday through Friday. Record warm high temperatures may be challenged. Here are those records for each of our climate stations:

Date Toledo Mansfield Cleveland Akron Youngstown Erie 06-29 100(1952) 96(1934) 94(2012) 98(1952) 99(1933) 90(2021) 06-30 97(1953) 94(1970) 95(1941) 96(1913) 94(1942) 92(1930) 07-01 98(1931) 98(1931) 95(2002) 97(1931) 96(1931) 94(2018) 07-02 98(2011) 97(1931) 97(1954) 98(1931) 98(1931) 94(1963) 07-03 100(1911) 93(2020) 98(1949) 97(1911) 98(1898) 93(1934)

CLE WATCHES/WARNINGS/ADVISORIES

OH...Heat Advisory from noon Monday to 8 PM EDT Thursday for OHZ003- 006-017. Heat Advisory from noon Tuesday to 8 PM EDT Thursday for OHZ007>014-018>023-027>033-036>038-047. PA...None. MARINE...None.