The state entered its second week of wilting, sweltering weather yesterday, but a welcome northern cold front was expected to provide relief by Thursday.
Yesterday's high of 96 degrees at 11 a.m. was the 38th time this year that the mercury has hit 90 degrees or better. The annual average is 31 days.
Showers in Westminster and a brief sprinkle downtown helped to cool temperatures a tiny bit in midafternoon, but by the evening rush hour, the thermometer was back up to 96 degrees.
The heat is caused by a "Bermuda high" -- a high pressure system sitting on top of the Southeast coast -- which is bringing hot, humid air up from the Gulf of Mexico.
That system is moving slowly to the South Atlantic and a cold front from the North is slowly moving south.
"The Bermuda high comes in and stays, and it builds and builds. Hopefully, the system coming from the Great Lakes will bring some relief with cool, dry air," said Amet Figueroa, a forecaster with the National Weather Service at Baltimore-Washington International Airport. "Thursday, we should see some cooler weather."
The city may get some thunderstorms today or tomorrow when the two systems clash, but don't expect the mercury to fall into the 80s until Thursday, Mr. Figueroa cautioned.
The type of high pressure system that brought the 104-degree temperatures to Baltimore on Sunday -- matching a 1930 record -- usually visits this area two or three times a year, Mr. Figueroa pointed out.
Sunday was the third day this year that the city has baked in 100-plus temperatures.
Today's forecast is a carbon copy of the past few days -- hazy, hot and humid.
Even the shade of night affords the area scant relief. Sunday's low was a warm 83 degrees at 4 a.m. and the mercury bubbled at 96 muggy degrees just before midnight.
"What makes this summer so unusual, it started in the spring," said Mr. Figueroa. "I think everybody is already worn out, and we still have August to go through."
Two people suffering from heat stroke were treated at Johns Hopkins Hospital over the weekend, said Dr. Keith Silverston, director of emergency medicine.
A number of people have fainted from the heat, according to Dr. Silverston. He suggests that people stay inside, reduce physical activities and drink lots of water.
Heat-related illnesses sometimes take a few days to affect people, and with the relentless barrage of high temperatures, more people will likely become dehydrated and susceptible to heat stroke and heat exhaustion, he said.
That includes the Baltimore Orioles. The team played in temperatures that hit 115 degrees on the field in Sunday's game against the Seattle Mariners.
Head Trainer Richie Bancells said that the players take sodium and potassium tablets to beat the heat. Eating a banana can also restore those lost minerals to the body, he noted.
Fans going to the game should wear light clothes and drink a lot of fluids, Mr. Bancells advised. But that doesn't include beer or other alcoholic drinks, which make people urinate frequently and results in a net loss of fluids, Dr. Silverston pointed out.
Even with record temperatures, Baltimore Gas and Electric Co. said that it did not have to use its energy-managment program that turns off air-conditioners of registered participants for 15 minutes every hour during critical peak demand hours.
Although BG&E; supplied a record 5,490 megawatts of electricity Friday -- breaking the 1988 record by 13 megawatts -- BG&E; spokesman Arthur Slusark said the utility has sufficient power resources to avoid the rotating cutoff of air-conditioners.
"We have more than enough energy stored up and more capacity than last summer because of the Bandon Shores 2 plant that went on line in May," he said.
About 9,300 BG&E; customers were without power for up to four hours over scattered areas of the region yesterday. The longer outages were attributed to failed transformers that had to be replaced, the company said.
On the average, BG&E; has between 500 and 2,000 customer outages a day, spokesman John Metzger said.
The dawn-to-dusk ban on outdoor sprinkling, car washing and pool filling that was imposed Friday will remain in effect for the next few days, said James Kapplin of the Department of Public Works.
How to beat the heat
Whether you are preparing to run a marathon or tending to the undergrowth in your backyard garden, health problems caused by summertime heat can be avoided.
The oppressive heat and humidity should never be taken lightly, experts warn. Thousands of people end up in emergency rooms every year because they ignore the danger posed by extremely hot, humid weather.
Here is some advice from experts on how to cope with the heat:
* Drink water, but don't wait until thirst sets in -- it may be too late. You should drink water before, during and after any outdoor activity. Also, wear a hat and T-shirt during exercise to help keep sweat from evaporating too quickly, and bring water along to drink while working out.
(One way to gauge fluid loss is by comparing weight changes before and after exercising. Urine color can also be used to determine how much fluid the body has to spare. If urine is darker than usual, it's a cue to start drinking more fluid.)
* Try to avoid strenuous work and exercise in the middle of the day. Athletes and people working outdoors are always vulnerable to the ravages of heat, especially if they are not used to exercising in a hot and humid climate.
* Watch infants and elderly people closely to make sure they are not developing symptoms of heat cramps, heat exhaustion and heat stroke.
* People with chronic medical conditions -- such as diabetes, high blood pressure and obesity -- should be especially careful. Certain medications, such as diuretics, may also cause problems when exercising or working outdoors.
* If a person loses consciousness during outdoor activities on a hot, humid day, seek medical help immediately. Lesser problems can usually be handled by moving to a cool place, resting and drinking liquids to replenish what's lost.
* Stay in the shade as much as possible.
* Wear cool, loose clothing.