FORECAST FOR DEKALB AND VICINITY, 7/23/08, NOON Today...sunny and pleasant. High of 78 degrees. Northeast winds around 10 MPH. Tonight...clear and pleasant. Low of 56 degrees. Winds becoming calm early. Tomorrow...sunny in the morning, increasing cloudiness in the afternoon. High of 81 degrees. South winds increasing to 10 MPH in the afternoon. Extended outlook...Friday through Tuesday... Friday...partly cloudy, warmer and more humid with a chance of a thunderstorm Thursday night into Friday morning, and then again Friday night. Warm and humid with a low in the lower 60s. High in the middle 80s. Saturday...variable cloudiness, warm and humid with scattered thunderstorms, mainly early. Low in the middle 60s. High in the middle 80s. Sunday...partly cloudy and less humid. Low around 60. High in the lower 80s. Monday and Tuesday...mostly sunny. Low in the lower 60s. High in the lower or middle 80s. **************************************************************************** CLIMATE DATA: Yesterday's high, 78 degrees; last night's low, 57 degrees. The average high/low temperature is 82/62. We have had no rain at the DeKalb campus over the last 24 hours ending at 7 AM this morning. Forecast was for 79/56. We have had 5.25" of rain this month. On average, we should see 4.26" of liquid equivalent by July 31. We have had 24.94" of liquid equivalent so far this year. By July 31, our average annual liquid total should be 21.88". **************************************************************************** SEVERE/HAZARDOUS WEATHER OUTLOOK: Nothing through Thursday. The risks for any widespread severe weather through the weekend is low. **************************************************************************** PRECIPITATION: Thursday night into Friday morning: .01"-.25", and 40% coverage. **************************************************************************** FORECAST DISCUSSION: This will be brief today as we take our system down for some unscheduled maintenance to check on a hard drive. We'll have weather.admin.niu.edu back up around 1 PM. I made no significant changes to the going forecast, except to better define precipitation timing and chances late this week. It looks like the best chances will be at our southern campuses Thursday night into Friday night, but the worst of that will stay to our southwest and south of the area. Then, Saturday morning, as the cold front comes through, a band of showers and thunderstorms comes through, perhaps, and then we turn nice for the rest of the weekend and the first half of next week. On the surface map this morning...a low near Buffalo, NY had a warm front east to northern New jersey before it heads into the Atlantic. A cold front trails the low into southern Kentucky and then westward into central Kansas, where it is already starting to come back north as a warm front. Ahead of this system, Strong to severe thunderstorms are expected in the northeastern U.S. today, southward through Virginia and the Carolinas, across much of the deep south and westward into Arkansas. A low over Saskatchewan with a cold front southwest into Montana will move into an area with high heat and humidity in the northern Plains. Along with fairly decent convergence and lift along the front, strong to severe thunderstorms are also possible from the Dakotas and Nebraska southeast into Iowa this afternoon through tonight. High pressure dominated the Pacific northwest and much of the western U.S. But the big story is, of course, hurricane Dolly, lashing the southern Texas coast with 100 MPH winds: BULLETIN HURRICANE DOLLY ADVISORY NUMBER 13 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL042008 1000 AM CDT WED JUL 23 2008 DOLLY VERY NEAR THE TEXAS COAST WITH 100 MPH WINDS...EYE SHOULD CROSS THE COAST IN A FEW HOURS... A HURRICANE WARNING REMAINS IN EFFECT FOR THE COAST OF TEXAS FROM BROWNSVILLE TO CORPUS CHRISTI...AND FOR THE NORTHEASTERN COAST OF MEXICO FROM RIO SAN FERNANDO NORTHWARD TO THE BORDER BETWEEN MEXICO AND THE UNITED STATES. PREPARATIONS TO PROTECT LIFE AND PROPERTY SHOULD BE RUSHED TO COMPLETION. AT 10 AM CDT...1500 UTC...THE TROPICAL STORM WARNING NORTH OF PORT O'CONNOR HAS BEEN DISCONTINUED. A TROPICAL STORM WARNING REMAINS IN EFFECT FROM NORTH OF CORPUS CHRISTI TO PORT O'CONNOR. A TROPICAL STORM WARNING AND A HURRICANE WATCH ARE IN EFFECT FROM LA PESCA TO SOUTH OF RIO SAN FERNANDO. FOR STORM INFORMATION SPECIFIC TO YOUR AREA...INCLUDING POSSIBLE INLAND WATCHES AND WARNINGS...PLEASE MONITOR PRODUCTS ISSUED BY YOUR LOCAL WEATHER OFFICE. AT 1000 AM CDT...1500Z...THE CENTER OF HURRICANE DOLLY WAS LOCATED BY RADAR AND A RECONNAISSANCE PLANE NEAR LATITUDE 26.0 NORTH... LONGITUDE 97.0 WEST OR ABOUT 30 MILES...50 KM... EAST-NORTHEAST OF BROWNSVILLE TEXAS. DOLLY IS MOVING TOWARD THE NORTHWEST NEAR 7 MPH...11 KM/HR. A WEST-NORTHWESTWARD MOTION WITH A SLIGHT DECREASE IN FORWARD SPEED IS EXPECTED LATER TODAY. ON THE FORECAST TRACK...THE EYE OF HURRICANE DOLLY WILL BE CROSSING THE COAST NEAR THE TEXAS/MEXICO BORDER IN A FEW HOURS. PERSONS ARE ADVISED NOT TO VENTURE OUTDOORS DURING THE RELATIVE CALM OF THE EYE BECAUSE WINDS WILL SOON INCREASE QUITE RAPIDLY. MAXIMUM SUSTAINED WINDS HAVE INCREASED TO NEAR 100 MPH...160 KM/HR...WITH HIGHER GUSTS. DOLLY IS A CATEGORY TWO HURRICANE ON THE SAFFIR-SIMPSON SCALE. STRONGER WINDS...ESPECIALLY IN GUSTS...ARE LIKELY ON HIGH RISE BUILDINGS. SOME ADDITIONAL STRENGTHENING IS POSSIBLE BEFORE LANDFALL. HURRICANE FORCE WINDS EXTEND OUTWARD UP TO 25 MILES...35 KM...FROM THE CENTER...AND TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 140 MILES...220 KM. PORT ISABEL AIRPORT JUST MEASURED 54 MPH...87 KM/HR SUSTAINED WINDS WITH GUSTS TO 70 MPH...113 KM/HR. AN UNOFFICIAL OBSERVER JUST EAST OF MATAMOROS MEXICO REPORTED SUSTAINED WINDS OF 65 MPH...105 KM/HR WITH GUSTS TO 119 MPH...192 KM/HR. MINIMUM CENTRAL PRESSURE REPORTED BY AN AIR FORCE RECONNAISSANCE PLANE WAS IS 964 MB...28.47 INCHES. DOLLY IS EXPECTED TO PRODUCE TOTAL RAINFALL ACCUMULATIONS OF 6 TO 10 INCHES...WITH ISOLATED AMOUNTS OF 15 INCHES...OVER PORTIONS OF SOUTH TEXAS AND NORTHEASTERN MEXICO OVER THE NEXT FEW DAYS. THESE RAINS WILL LIKELY CAUSE WIDESPREAD FLOODING ACROSS PORTIONS OF SOUTH TEXAS AND NORTHEAST MEXICO. COASTAL STORM SURGE FLOODING OF 6 TO 8 FEET ABOVE NORMAL TIDE LEVELS...ALONG WITH LARGE AND DANGEROUS BATTERING WAVES...CAN BE EXPECTED NEAR AND TO THE NORTH OF WHERE THE CENTER MAKES LANDFALL. ISOLATED TORNADOES ARE POSSIBLE OVER PORTIONS OF SOUTH TEXAS TODAY AND TONIGHT. A tropical wave over the far eastern Atlantic is too far north to develop into a tropical system, due to cooler water underneath it...for now. For more information, please see http://www.nhc.noaa.gov. Our forecast problems...the system coming through Friday and Saturday morning. Today through Thursday evening...high pressure is in control, moving across the area this evening and then to our east tomorrow, which will change our winds from northeast today to southerly tomorrow and bring in warmer and eventually more humid air by Friday. But overall, with the exception of increasing clouds by tomorrow afternoon, we'll see two great summer days. Look for highs near 80 today, and in the lower 80s tomorrow, with low humidity and a comfortable low tonight in the middle to upper 50s. Thursday night-Friday morning...as the system in the Plains approaches with a warm front that will develop this evening, thunderstorms across Iowa and Missouri will head across central Illinois, probably nicking our southern campuses (IE, DeKalb and Naperville), with the heaviest rain along a Peoria-Bloomington southward to an I-74 axis across central Illinois. Southerly winds, however, will bring back the humidity, so expect a muggy low in the middle 60s tomorrow night. Friday...much of the day should be dry, but warm and humid as we will be in the warm sector of this system. Look for highs at least into the middle 80s, and maybe higher. Which isn't terrible, and heat indicies will barely crawl into the caution range...typical for this time of year. Friday night into Saturday morning...the cold front comes through early Saturday and bad timing of that front, coupled with less than stellar upper flow and dynamics means that the system might even come through dry. But I will maintain scattered thunderstorms, as there should be enough lift for at least scattered storms to move across the area. These shouldn't be a big deal. Much of Saturday and the first half of next week...you can't ask for better this time of year. Humidity will drop as Saturday goes on, and then the first half of next week may be dry except for a chance of a thunderstorm on Wednesday due to a cold front coming through. Then we may turn warm and largely dry for the back half of next week. So, look for slightly below average temperatures and below average precipitation over the next 10 days. A relatively quiet period...which I think we all need. ******************************************************************************* Gilbert Sebenste ******** (My opinions only!) ****** Staff Meteorologist, Northern Illinois University **** E-mail: sebenste@weather.admin.niu.edu *** web: http://weather.admin.niu.edu ** *******************************************************************************