SOUTH LAKE TAHOE, Calif. — Lake Tahoe is in the grasp of another warm temperature surge and weather officials have upgraded to a red flag warning and have and lengthened the duration.

After issuing a fire weather watch on Tuesday, the National Weather Service in Reno on Wednesday morning upgraded to the warning that goes into effect at midnight and lasts through 10 p.m. on Thursday due to gusty winds and low humidity.

Southwest winds are expected to be in the 15-20 mph range in the afternoon with gusts up to 30-40 mph, the service said. Higher gusts are expected in wind prone areas and along exposed terrain.

The humidity is about 5-15% which means the conditions are prime for a spark to quickly grow out of control before first responders can arrive on scene.

Officials advise against any outdoor activities that could cause a spark near dry vegetation such as yard work, target shooting, or campfires.

Check weather.gov/reno for updates and livingwithfire.info for preparedness tips.

South Lake Tahoe reached a high of 89 at 1:08 p.m. Tuesday which tied the record set in 1993. The normal temperature for the time of year is 81. The record low for the time of year is 31 set in 1989.

The South Shore may set another record on Wednesday with the forecast calling for highs in the upper 80s while the record is 89.

The temperature is forecast to drop into normal ranges for the time of year on Thursday and Friday before rising to the mid 80s for the weekend.