So maybe we won't hit 100 degrees in Baltimore today after all. The National Weather Service forecast office in Sterling has tweaked its forecast a bit in response to new model runs. They're now calling for a high at BWI-Marshall Airport of only 95 degrees, down from the 98 they were predicting last night.

(UPDATE, 11:45 a.m.: Just as I post this, the NWS bumps the BWI forecast high today to 97 degrees. New model run, I guess. Stay tuned.)

UPDATED UPDATE, 2:45 P.M.: Tweaked again. The forecast high for BWI is now 94 degrees. The Heat Advisory  has been lifted. 

There's some acknowledgement in the morning forecast discussion , however, that their model guidance has been "running too cool," so they have not gone as low as the models suggest they should. Your weather blogger has contended for some time that Sterling routinely undershoots Baltimore's summer heat wave highs by 2 or 3 degrees. We'll see how well they do this time.

The record high for Baltimore for this date is 97 degrees, set in 1908. That may be a bit harder to crack today than it seemed at this time yesterday. But it's not impossible.

In any case, humidity levels will remain high, with dew points in the low 70s. So they're not changing their forecast on Heat Index readings for this afternoon. They're still calling for us to top out between 100 and 105 degrees. 

That's why we remain under a Heat Advisory in Central Maryland today (Tuesday).  From Baltimore, Harford, Howard and Montgomery counties south to the Potomac, and on the Eastern Shore, heat and humidity will combine to increase the risk of heat-related illnesses. Nine people were seen in Baltimore emergency rooms Monday with heat-related illnesses, according to Brian Schleter, of the city Health Department.

We're also under a Code Orange Air Pollution Alert in Central Maryland. We never did reach Code Red levels, as had been forecast for Monday.

The predicted cool-off is still en route. Forecasters had said we'd drop to the high 80s in Baltimore by Wednesday. But that's been bumped to 92 degrees, with a continuing low risk of showers and storms. The promised cold-front passage is now on the agenda for Wednesday morning and afternoon, moving from north to south.

Winds from the northwest behind the front will finally bring daily high temperatures down into the mid-80s Thursday through Saturday, with noticeably drier conditions. That's actually just a shade below the normal values for this time of year. Should feel great.

The heat and humidity start to return on Sunday as the high moves off the coast and we get the return flow from the south. But forecasters are promising "no big heat waves expected through Monday."

(PHOTO: Reuters, Laszlo Balogh)