NWS/JAX

Weather Underground

...HEAT INDICES 105 TO 110 DEGREES THIS AFTERNOON...

Plan your trip Local Radar Detailed Forecast

Today:Mostly sunny in the morning, then partly cloudy with a 30 % chance of showers and thunderstorms in the afternoon. Highs in the mid 90s. Northwest winds 5 mph increasing to west 10 to 15 mph in the afternoon. Heat index readings 104 to 108 in the afternoon.

Tonight: Partly cloudy with a 20 % chance of showers and thunderstorms in the evening then mostly clear after midnight. Lows in the mid 70s. West winds 5 to 10 mph.

Highs in the mid to upper 90s this afternoon will push heat index into the 105 to 110 degree range. use extra caution while outside today.

Scattered showers and thunderstorms are expected during the afternoon and evening with most of the activity across the inland areas. The main concerns with isolated stronger storms will be frequent lightning and strong down burst winds.

Forecast Details: surface ridge axis is over south central Florida with middle level high pressure system over central Georgia area. A weak frontal boundary is noted in MSAS analysis over Georgia and central South Carolina where scattered convection has been ongoing all night though convection is largely decreasing in intensity and coverage. Mean low and middle level flow is southwesterly about 5-10 knots per RUC analysis. Temperatures and dew points are elevated still due to the affects of the middle level ridge and the warmer than normal air mass. Temperatures are in the upper 70s and lower 80s and dew points are mostly in the middle 70s at this time. Patchy fog is possible over northeast Florida through sunrise.

Today the affects of the middle level ridge over the region will keep the rain chances below normal with 500 MB temperatures near -5/-6 c. Southwesterly flow expected to help the West Coast sea breeze along and delay the East Coast sea breeze. Will advertise probability of precipitation around 20-30% over northeast Florida and 30-40% in southeast Georgia closer to the weak front. Used a blend of MOS guidance for probability of precipitation but went above in northeast Florida based on mesoscale models. Highs in the middle and upper 90s will allow for heat index of up to 104 to 109 just below heat advisory conditions. Record highs may be met at some inland stations, if not with 1-2 degrees.

Tonight isolated evening showers and storms expected with convection dissipating late. Lows in the middle 70s expected with some upper 70s possible near the coast.

Today's Pollen Levels: 4.2 Low Medium (on s a scale to 12); Predominate Pollen: Grass.

For additional information visit the National Weather Service in Jacksonville website on the internet at http://www.srh.noaa.gov/jax/