Hot times: Record watch

On an afternoon more typical of July in northern Arizona, the official temperature in Philadelphia is challenging a record for the second consecutive day.

At 3 p.m., the thermometer at the airport was reading 89.1 degrees, or 0.9 degrees shy of the all-time high set in 1929. Yesterday's high, 87, tied the record for the date.

And that air out there is bone dry. The relative humidity at 3 was a very un-Philadelphia-like 20 percent -- about what it was at Grand Canyon, Ariz.

The dry air plus brisk southwest winds moved the National Weather Service to post a "red flag" alert for fire danger. The weather service warned that any brush fire could spread in a hurry under these conditions.

Although the early April heat spell in 1929 arguably was more impressive, this is going to end up being the warmest first week in April ever in Philadelphia.

The average April 1-7 temperature is going to be about 65 degrees. Even though the temperature reached 87, 90 and 90 on three consecutive days in 1929, the seven-day average that year was 61.3.

This will all come to an end later tomorrow with the passage of a cold front that might kick off some strong thunderstorms.