If you look at the forecast highs for Sunday, North Georgia is only expected to reach 60 degrees, while surrounding areas, including Tennessee, Alabama, and South Carolina will be close to 70. In fact, you would have to travel north to Boston, or northwest to the Great Plains to see similar low temperatures. The reason for the anomaly is the buildup of a classing wedging situation.

For the last few days, our weather has been dominated by a high pressure system centered over Eastern Canada. This has brought dry air down the East Coast. The low dewpoints allow the air to cool at night (last night’s low of 45 degrees, for example), but still warm up during the day.

On Saturday evening and Sunday, a low pressure system will approach from the west, bringing higher dewpoints, warmer air, and a chance of rain. Because the high is still bringing in dry air, and because the dry air is heavier than the more humid air, it will get trapped underneath the warm front.

The net effect will be to provide a cloudy day, where the temperatures never get a chance to recover from the cool nighttime temperatures. If there’s a positive side, the wedge will also prevent the worst of the rain, which could reach an inch or more to our west from getting into Georgia, particularly East and Central Georgia.

So, here’s my prediction for Sunday: If you see the temperatures rising much above 60, then expect some rain. The warm front will have won out over the wedge. On the other hand, if it stays cool, the rain will be minimal: less than a tenth of an inch.

Forecasters have been predicting a major rain event that could bring up to 3 inches of badly-needed rain to Atlanta. The Weather Service has issued a flood watch. Radar and satellite views over the last 24 hours show approaching rain, but it never seems to make it to Atlanta.

The storm’s slower than expected advance has been stalled by high pressure to our north. Heavy cool, dry air in north Georgia produced a wedge situation, forcing the lighter warm moist air upward, and wringing the moisture out. The wedge is part of the reason why Gwinnett didn’t record any rain yesterday, while down in Hampton, the Golden Corral 500 was rained out. They have rescheduled it for today, but I don’t think they will get it in.

The HPC is predicting that we could get up to two inches of rain from the storm, with most if it coming after sunset tonight. It should start to clear out by Tuesday midday, and high pressure will follow, bringing fair weather for the remainder of the week.

Today is the first day of spring, but the warm weather we saw last week may stay away through the end of the month. long-range forecasts say we should expect lower than normal temperatures and below normal precipitation through April 2nd. One forecast I saw predicted highs in the 50s to low 60s, and no high temperature above 70 degrees until the first of the month, when our normal daytime high should be in the upper 60s.

Today’s high temperature of 39 degrees is the coldest high daytime temperature we’ve seen since … last Sunday. However, prior to that, you would have to go back to January 17th, 2005 to see a day when the high temperature was lower. The two cold days mark bookends to a week that also saw the year’s highest temperature to date on Thursday, with a high of 72.8 degrees.

Today’s cold was amplified by the wedge effect, which trapped the morning’s cold temperatures under warmer air aloft. However, we were spared the worst of the weekend’s cold. When I got up this morning, it was 32 in Atlanta, and 21 in Chattanooga. However, 40 miles to the northwest, in Altamont Tennessee, the temperature was a frigid 9 degrees.

After another cold day on President’s day, expect things to warm up, although stay rainy through Thursday. Friday looks to be the nicest day of the week, and then a pattern change brings cold, dry weather in, quite possibly through the end of the month. Both the 6-10 day and 8-14 day forecasts call for colder and dryer than normal temperatures through the period which ends on March 5th. This is especially true for the end of the period, when highs could struggle to make 50 degrees, and overnight lows will be in the mid 20s.

The long-range forecast for March as a whole calls for a slight chance of above normal temperatures, and normal rainfall. It seems like groundhog Beauregard Lee needs to get busy if he wants to salvage his prediction of an early spring.

Even though it’s still relatively early in December, the weather is acting like the middle of January. For this time of the season, the normal high should be around 55 degrees; we’ve been lucky to see 50. And, the next few days aren’t likely to be any better.

Tomorrow, the weather takes a turn for the worse, and brings us a chance of freezing rain or ice. We have a similar situation developing to what we had last week, with a high pressure system in the northeast, and a low approaching from the southwest.

This type of weather brings on what is often called “the wedge” by local forecasters, but is also known as cold air damming. What’s happening is that the high pressure system in the northeast is moving cold air into our area. Meanwhile, the low is bringing in warmer, moist air from the southwest. The cold air gets trapped underneath the warmer air by the Appalachian mountains, and gives us a cold, east wind, cloudy weather, and the chance of freezing rain.

The question is whether it will get cold enough due to the wedge to cause the precipitation to freeze, or whether it will stay warm enough, just like last week, to just give us a cold rain. The National Weather Service is betting that the freezing stuff stays to our north, although it might reach Gainesville. The highest risk of a problem is Wednesday evening and early Thursday morning. Later in the day Thursday, temperatures should warm enough to give us just rain.

The wedge is expected to dissipate by late Thursday evening, and bring us sunny weather by Friday, and into Saturday. Then, another low approaches on Saturday evening, and brings us another chance of snow or freezing rain, although without the wedge.

The good news is that after these two systems move through, things look a bit nicer for Christmas week. But, it’s going to remain colder than normal, with a relatively dry period between December 21st and the 27th.

It’s too early to say Spring is around the corner, but the good news is that the sun is already starting to set later in the evening, and a week from tomorrow is the shortest day of the year.

Late Spring is a time of rapidly changing weather, and the last two weeks and the week coming up are perfect examples. Completely different weather patterns highlight the old saw, if you don’t like the weather, stick around, and it will change.

East coast weather the week before Memorial Day was dominated by a major upper level low pressure system in New England that brought in cold air from Canada, and for Atlanta, kept temperatures closer to what we would see in mid April rather than late May. May ended the month with only 1.34 inches of rain, less than half of what we would normally expect. Temperatures were on the cool side as well, with the average temperature about 3 degrees below normal.

Then, beginning (natch) over the holiday weekend, the weather pattern began a big change, with a cold front from the northeast running up against a stationary front stalled across middle Georgia. This caused a wedge situation, with cool temperatures, seemingly never-ending light rain, and winds out of the east. The National Weather Service reported that the first three days of June were among the coolest ever.

At the beginning of the weekend, forecasters were concerned about a tropical wave bringing in heavy rains to the Atlanta area. However, a weak high pressure system over the area kept the rain to our south, and left us with typical Atlanta summer weather - hazy, hot and humid, with not many changes predicted for most of the upcoming week. As is typical for an Atlanta summer, there is a chance of popup thundershowers throughout the week.

It’s all part of the normal shift to our summer weather pattern. The tropical weather pattern is under way somewhat early this year. Dr. Gray has issued an update to his hurricane activity forecast, increasing the number of named storms from 13 to 15, and the number of hurricanes from 7 to 8.

The National Weather Service long range forecast through the end of the third week in June calls for above normal temperatures, and above normal precipitation.