How hot is Baltimore? Well, we don't quite know

Like a feverish patient with nary a nurse to take her temperature, the city of Baltimore has sweated through a near-record heat wave without anyone knowing for sure just how hot it really is.

Since Jan. 1, 1908, the National Weather Service had provided the official measure of hot and cold in Baltimore from the roof of the Custom House at Gay and Lombard streets.


But a $10 million renovation of the building damaged the service's 1940s-era weather equipment three months ago, and federal officials say it could be spring before the city's temperature can be taken again.

"The way it is now, you don't really know what's going on with the weather in downtown Baltimore," says Ray Muller, a 46-year-old hardware salesman who runs a small weather service out of his Finksburg home. "This is a matter of respect for the city of Baltimore."


Sun-drunk Baltimoreans in need of a weather fix can still get it from the weather service data at Baltimore-Washington International Airport.

If temperatures next to the runways exceed 90 degrees for four more days, the current heat wave will set a record.

But BWI is five miles outside the city limits, and that is too far to suit scientists worried about the absence of weather data from ++ downtown.

After all, what if meteorological history were being made, and no one was there to record it?

"I hate to hear that's happening," says David Robinson, a professor of meteorology at Rutgers University and the state climatologist of New Jersey. "I'm a real champion of continuity. The fact that the temperature has been taken at one position for so long permits you to closely study the local weather."

"The integrity of the climatic record . . . is the problem," Bill Ryan, a research scientist in the meteorology department at the University of Maryland's College Park campus, said. "You want to keep the data record as uninterrupted as possible, and that's not happening."

Mr. Ryan said that the lack of official weather data for the city is "not a big deal." It does not affect, for example, the air quality forecasts he makes every day for the Maryland Department of the Environment.

Still, Alan Robock, the state climatologist of Maryland, says "a number" of potential research projects -- including studies of energy use, regional air pollution, and sea breezes -- could depend on accurate temperature data from Baltimore. And climatologists who want to compare suburban and city heat (the so-called "urban heat-island effect") may have to look outside the Baltimore area for complete data.


"Unfortunately, in this case, it seems to me that there's nothing we can do about it," says Bob Hudson, a professor of atmospheric chemistry at the University of Maryland College Park.

The weather service insists it is not to blame for breaking a tradition of downtown temperature taking that dates back to 1870s.

Meteorologists blame the U.S. General Services Administration, which is renovating the Custom House, for cutting off power to the weather instruments this spring without telling the weather service first. John Thompson, a GSA spokesman, declined comment on that claim.

"One day I came in, and we thought the equipment at the Custom House just wasn't working," says Jose Marrero, a

weather service meteorologist based at BWI. "It wasn't till we got down there that we saw what had been done."

The power shutdown damaged equipment that is too old to be fixed, he says. New weather equipment probably won't arrive until the completion of renovations, which is scheduled for April next year.


In the meantime, forecasters are telling media outlets and weather buffs that they can estimate a reasonably accurate Custom House temperature by adding three or four degrees to the BWI reading, Mr. Marrero said.

Mr. Travers said he has thought about taking this opportunity to move the weather service's measuring site away from the Custom House roof. At 100 feet above ground, weather instruments there are susceptible to wind and heat from the asphalt on the roof. But scientists' need to compare temperatures across the decades will compel the weather service to continue using the building, he said.

Mr. Robinson, the Rutgers meteorologist, says Baltimore is the rare major city where the temperature is still taken downtown. After World War II, the National Weather Service moved the weather measurement operations in several metropolitan areas from downtowns to nearby airports, he said.

The meteorologist said he worries that historic measurement sites like the Custom House may become casualties of efforts to consolidate offices of the National Weather Service. Forecasting responsibility has already been transferred from BWI to headquarters outside Washington.

"When you have a major reorganization like theirs, things like the Custom House seem to slip between the cracks," Mr. Robinson said.

Any citizen desperate for a downtown temperature can call Bell Atlantic, which receives its data from Electronic Telecommunications Inc. in Atlanta. Bill Estes, a technical support engineer for ETI, said his company maintains a working thermometer on the Custom House roof, but temperature readings from it "are not to be considered official."


The particulars of weather measurement, however, matter little to Baltimore residents like Doug Clark and Phil Wagner, the doormen at the Tremont Plaza in the 200 block of St. Paul St.

Mr. Clark, 28, and Mr. Wagner, 27, say all they know about the weather is that it's too hot to work in the blue polyester vests their hotel requires.

"This is miserable and sweaty, but the weather reports have been pretty accurate," Mr. Wagner said. "All I hear is that it's going to be above 90, and that's what it is."


When temperatures rise over a city, a weather phenomenon " called a "heat island" effect creates a dome of heat that makes it hotter in the city than in surrounding suburban areas.

* Like street and sidewalk surfaces, stone or brick buildings act as heating mechanisms by absorbing the sun's rays, storing the heat temporarily and then reradiating the heat back in to the air.


* Glass windows and metal buildings reflect heat to other buildings, intensifying the sun's rays until they are absorbed.

* About half the sun's energy is typically used to evaporate moisture, but a lack of surface water in the city because of dry weather and efficient drainage and sewage systems means a higher percentage of the sun's energy is creating heat.

* A lack of vegetation in the city means less moisture and nmore heat, because vegetation draws moisture to the surface and converts the sun's rays to energy, not heat.

* Automobile exhaust and other pollution trap heat.