Update #1, 12:15 PM: Typo in low last night. It should have read "54", not "64". Apologies for the inconvenience. Notes: I will be out of the office on Thursday and Friday of this week, for the 4th of July holiday weekend. A forecast will be sent on our "weekend" list each day, and updated on our website continuously. FORECAST FOR DEKALB AND VICINITY, 7/1/09, 10:50 AM Today...cloudy, breezy and unseasonably cool with scattered very light showers, sprinkles, and drizzle. High of 65 degrees. North to northwest winds 10-20 MPH. Tonight...cloudy. Low of 53 degrees. Northwest winds around 10 MPH. Tomorrow...cloudy early, then gradual clearing throughout the late morning and afternoon. High of 75 degrees. Northwest winds 10-20 MPH. Extended outlook...Friday through Tuesday... Friday...increasing cloudiness. Low in the upper 50s. High around 80. Saturday...variable cloudiness with a chance of a shower or thunderstorm later in the day. Low around 60. High in the upper 70s. Sunday...variable cloudiness with a chance of a shower or thunderstorm. Low around 60. High in the lower or middle 70s. Monday...partly sunny. Low in the middle 50s. High in the upper 70s. Tuesday...partly cloudy. Low around 60. High in the lower 80s. **************************************************************************** CLIMATE DATA: Yesterday's high, 65 degrees; last night's low, 54 degrees. The average high/low temperature is 82/58. We have had a trace of rain at the DeKalb campus over the last 24 hours ending at 7 AM this morning. Forecast was for 68/54 with a trace of rain/drizzle and 40% coverage; drizzle/rain coverage was a little more than that. We have had a trace of rain this month. On average, we should see 4.26" of liquid equivalent by July 31. We have had 25.97" 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 next Thursday that would cause significant problems. There is a chance of a non-severe thunderstorm during fireworks on the fourth of July, but it is still too far away to tell how great that chance is. **************************************************************************** PRECIPITATION: Through 6 PM today: a trace to .05", and 50% coverage. **************************************************************************** FORECAST DISCUSSION: No significant changes to the forecast. The weekend system still looks like it won't be a washout, but some outdoor weekend activities may be threatened briefly on occasion. However, most of the rain stays south of the area this weekend. Early next week will be dry and comfortably warm, but then we get steamier towards the back half as southerly winds and humidity return to the area. On the surface map this morning...a low just northeast of Lake Huron has a slow-moving cold front from there to eastern North Carolina, and then westward across southern Tennessee, Arkansas to eastern Colorado. This system will produce clouds, drizzle, light rain, and a very cool day across the Great Lakes and northeastern U.S., while assisting strong to severe thunderstorms in Colorado. Temperatures dropped well down into the 40s across far northern Wisconsin and northern Minnesota. A low in eastern Montana had a warm front southward to northeastern Colorado, and a cold front westward into northern California. This system will produce scattered thunderstorms, some severe, from Montana to western Nebraska. Scattered thunderstorms will continue in the southwestern U.S., in the tropical airmass there. And speaking of the tropics, things will be quiet there through Saturday, but a disturbance in the eastern Caribbean will need to be watched for early next week. Our forecast problems...the system over us now, and then the one this weekend. Today through tomorrow...the occasional drizzle and very light rain we have been seeing over the past 24 hours will come to an end later this afternoon as the upper low to our northeast weakens and begins to head eastward. Meanwhile, the clouds should gradually break up tomorrow...though probably not as soon as had hoped for earlier. Given highs yesterday, I dropped ours down into the middle 60s for this afternoon, a good 15-20 degrees below seasonal averages. Tonight...lows again of 53 or 54 degrees are very likely. But tomorrow's temperature forecast is not of good confidence. We might not see sunshine until afternoon, and even then, there will be quite a few clouds around. So...I dropped highs in the middle 70s, but that could bust if clouds break up later than forecast, keeping temperatures cooler. Saturday through Sunday...a weak trough/cold front very slowly moves through the area this weekend. Models are showing this to be a very marginal setup, but they flip back and forth with scattered showers and thunderstorms both Saturday and Sunday, mainly in the afternoon hours. So, I will keep the forecast as is...and hopefully things become clearer by Friday. Do have an alternate plan in case you get a brief downpour outside. Look for highs in the 70s on Saturday, and around 75 on Sunday IF cloud cover on Sunday doesn't keep us cooler. Either way, no significant heat problems this 4th of July weekend, and that's a good thing! Next week...Monday through Thursday look dry and seasonably warm...but things start to get uncomfortable around Wednesday as southerly winds start bringing back some humidity, which magnifies on Thursday, before a cold front hits around Friday. However, that cold front might be pushed back until next weekend...we'll see. Either way, through Wednesday, we're looking good with highs slowly warming through the 80s, and lows around 60. All in all, not bad. Just watch for scattered showers and thunderstorms this weekend...that should be pretty brief, under an hour and mostly in the afternoons. Look for much below average temperatures today, below average through Friday, and then near average through the middle of next week, before going above average by next Friday. Rainfall will be spotty, but generally be below average over the next 10 days. Localized areas might see heavier rainfall, however, in slow-moving thunderstorms. Have a great holiday weekend all! If all goes well, I'll be back on Monday. ******************************************************************************* Gilbert Sebenste ******** (My opinions only!) ****** Staff Meteorologist, Northern Illinois University **** E-mail: sebenste@weather.admin.niu.edu *** web: http://weather.admin.niu.edu ** *******************************************************************************