Archive: July, 2010
If you live west or north of the city, normally take the Schuylkill Expressway, and you managed to drive into town this morning, congratulations.
You made it through quite a storm, a renegade that wrung out a quick 2 inches of rain and quickly engorged some of the waters coursing through parts of the region and set off flash flooding.
At 8:15 a.m., Frankford Creek was flowing at 28 cubic feet per second. At 10:45, the flow had raged to 10,100 feet per second.
On Friday, Pennsylvania's Department of Environmental Protection announced that it was officially worried about a developing drought.
The atmosphere must have taken it personally.
Since that release was issued, close to 2 inches of rain has fallen in Philadelphia, and more elsewhere.
In its weekly update , the government's Climate Prediction Center is saying that a La Nina cooling event is "developing" in the equatorial Pacific and it's looking more as though La Nina is going to rule.
The Pacific long since has exited the state of El Nino, an anomalous warming. Sea surface temperatures in the key El Nino-La Nina tracking region warmed significantly in the fall and reached a peak at the end of the year when they were about 2.5 degrees Fahrenheit above normal.
They have fallen steadily since April, and for the last month have averaged about 1.3 degrees below normal. That's low enough to qualify as a La Nina state, but to qualify as a full-fledged La Nina the cooling would have to persist into January.
Although no drought advisories have yet been issued, the state of Pennsylvania is officially worried.
The Department of Environmental Protection says the inter-agency drought task force, which includes the National Weather Service and the U.S. Geological Survey, will convene July 21 to assess the dry facts.
Through yesterday, for the last 30 days rainfall was below normal in every county in Pennsylvania, New Jersey and Delaware. Philly rainfall was about a third of normal.
In the final standings, yesterday was the hottest day in 15 years, barely out-roasted by July 15, 1995, and the fourth-warmest ever.
The high on both those days was 103, but the low yesterday officially was 80 at 11:59 p.m., compared with 81 on July 15, 1995.
Thus, yesterday's average temperature, 91.5 at Philadelphia International Airport was a shade lower than the 92 of its 1995 rival.
Heat waves have been called slow-motion disasters. They lack the drama of hurricanes or tornadoes, yet heat has been far deadlier than either.
Today the spotlight is off the heat around here, since the temperatures are going to settle for the low 90s rather than the attention-getting low 100s. But this is going to be an oppressive and potentially dangerous day as heat continues to accumulate, and the nights to a poor job of heat removal.
No one knows for certain how many people die in heat waves -- or, for that matter, how many have died in this one so far in Philadelphia. Dr. Donald Schwarz, the city health commissioner is certain only that the current total, five, is an undercount.
No records will be set today or for the next several days, but even though the temperature is going to be 10 degrees lower than yesterday's, this afternoon will match yesterday afternoon for discomfort.
A high of 93 won't get nearly the attention of 103, but for the heat-vulnerable today actually may be more dangerous.
The invisible enemy, water vapor, is building into the atmosphere over the region, and later today the heat indexes are forecast to approach 100, almost exactly where they were at the peak of yesterday's heat.
At 2:45, the temperature did reach 90 at Philadelphia International Airport, meeting the technical criterion for sustaining the heat wave, now in its fifth day.
With a low of 76 this morning, the average temperature of 83 was 6 degrees above normal. Since June 1 Philadelphia temperatures now have been above normal for 33 of 38 days.
Parts of the region did catch a break this afternoon with a renegade cloud cover from nearby showers holding down temperatures and heat indexes. The National Weather Service took down the heat warning late in the day.