This sundog occurred Friday night over Lexington and there is a companion sundog to the left, but it is out of the frame. The bright spot to the far right is a reflection off our “Big Blue” building.

Sundogs form when a couple unique conditions are present. Cirrus clouds are the atmosphere’s highest clouds and are composed of small ice crystals. These ice crystals are were the sun creates the show.

When the sun is close to the horizon and there’s a significant layer of cirrus clouds, which should be noted are curving towards the horizon, sunlight will do 3 things: 1) be reflected at a predictable location causing the bright spot, 2) refracted at the same spot causing a rainbow, and 3) scattered throughout giving the sundog a general reddish cast.

While not rare, sundogs are uncommon and have been heralded as both good and bad omens by ancient peoples.

Precipitation, or lack thereof.
The Daniel Boone National Forest averages between 43 inches a year in the northeastern section to 53 inches in the southwestern section around the Big South Fork. Currently, the forest is in a precipitation deficit of around 4-8 inches. With the approaching fall and the driest period of the year, the forecast is for a seriously dry time in the woods. This is especially true to south and east, but the high ridges are dust dry now.

The most problematic aspect of a drought this time of year is forest fire hazards. After trees drop their leaves under cloudless skies, the forest floor experiences direct sunlight and high evaporation rates. This produces abundant fuel for forest fires.

So if you’re planning a trip this autumn, be careful with camp fires and consider using stoves for cooking and battery candles for illumination. The following discussion looks at national maps of drought severity and outlook.

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Postscript
Ike’s precipitation never made it to the Daniel Boone. The winds did however. Hurricane force winds were recorded in Louisville, Kentucky and a strong wind advisory was posted for Lexington and the Daniel Boone. We’ll have to wait and hope for another storm to bring much needed rain to the state, though we wish for no dangerous hurricane.

Current Track for September 11
It was 47 years ago today that Hurricane Carla made landfall and battered the central Texas coast with wind gusts to 175 mph, and up to 16 inches of rain. Carla also spawned a tornado which swept across Galveston Island killing eight people. The Category 4 hurricane claimed 45 lives and caused $2.22 billion dollars in damage.

Forecasters haven’t directly compared Ike to Carla yet, but this hurricane will most likely impact Kentucky. After making landfall Friday, Ike should swing northest north and aim for Kentucky and the Daniel Boone National Forest. The final track however has yet to play out, but if the bluegrass gets under this tropical depression, the state undoubtedly will do some catching up on the meager precipitation it has received this summer.

On average, the central part of the state receives about 11 inches of rain in the summer, however only 8 inches has fallen from June-August and none so far in September. In September, one of the bluegrass’s driest months, rainfall totals average about 3 inches. Last September, less than one inch of rain fell that month. Bone dry.

Enter Ike
A storm of this magnitude could definitely bring 3 inches of rain to the bluegrass. It could bring 6 inches. If it strengthens to a category 4 storm above the warmest section of the Gulf of Mexico as predicted, it will contain an enormous amount of energy and water vapor. Hurricanes this strong produce more energy in a day than the U.S. produces at all power plants in a year. That’s a lot of juice and Ike has to go somewhere.

Hurricanes need over 80-degree F surface water temperatures to exist. Every degree above that is like adding gasoline to a fire.
Below is a map of current surface water temperatures