It’s not exactly the news people want to hear days before a holiday weekend, but gas prices have gone up. In Tullahoma the average price per gallon of gasoline yesterday was $3.49 a gallon, while in Manchester it is $3.50….But that’s 23 cents lower than the national average, with is sitting at $3.73 per gallon. With soon-to-be hurricane Issac heading towards the coast, prices could even spike even higher in the coming days. In anticipation of the storm, oil companies are evacuating their rigs in the Gulf of Mexico. Experts’ estimate 75 percent to 90 percent of gulf oil production could be shut down.