ENHANCED THREAT FOR THE SPREAD OF FIRES TODAY. Minimum relative humidity values will fall to between 25 and 30 percent this afternoon across portions of northw...estern Maryland east of the Allegheny Front, the Shenandoah Valley, central and northern Virginia and central and southern Maryland from Baltimore southward through the Washington DC metro. Sustained southwest winds between 15 and 20 mph with frequent gusts of 20 to 25 mph are also expected during this time. The combination of gusty winds, low relative humidity and very low fuel moisture will enhance the threat for the spread of fires this afternoon into early evening. Residents are urged to exercise caution handling any potential ignition source, including machinery, cigarettes, and matches. Be sure to properly discard all smoking materials. Any dry grasses and tree litter that ignite will have the potential to spread quickly. Please check with local officials regarding any open burning laws.