The forecast for today’s Friday the 13th includes very wet conditions across much of the Southeast this afternoon and early evening, as a disturbance and frontal system meander across the region. Low accumulation spots on the order of 1-3 inches then includes the Moderate Impact spot, where some people could see slippery roads and slightly hazardous travel weather. Heavy Impact status is expected in much of the 3-6 inch accumulation stripe, where there will be fair travel delays. I am confident in a good 3-6 inch accumulation in the darker blue, and a 6-12 inch plus snowfall over southern Wisconsin, much of Iowa, extreme northwest Missouri, extreme southeast Nebraska and northeast Kansas. Snowfall is expected to be heavy, and, combined with winds, will make travel dangerous (see Impact Scale below). Unnecessary travel is not advised. The only reason I do this is for the wind- very high winds will make whiteout conditions common in rural areas, and long-lasting travel delays will stem from those areas.

For that reason, earlier this year, we developed our Exclusive Impact Scale, where I can identify areas where travel may be hazardous, among other things, depending on the season. When done right, business forecasting can make your business more profitable. The British Isles for instance lying on the western edge of Europe, with the jet stream taking aim from across the Atlantic and the Gulf Stream conveying warm air to our shores, is much more difficult to measure. Surface Analysis indicates that much of the country is waking up to a cold morning today, with a strong high pressure system letting the cold air flow across the eastern half of country. My forecast for this system involves a Low Impact forecast for much of the region that will see some precipitation that is not wintry from this system. Other areas of the world however are much more changeable and harder to predict.

This is the tricky part, because this involves the areas right along the rain-snow line, something that troubles may forecasters and such rain-snow line forecasts are prone to ‘busting’, or failing. It looks like this may be the result of a low pressure stationed around the Texas/New Mexico region. I marked down generally low probabilities for much of the impacted region simply because of the lack of significant snow. The Plains will be baking in 100 degree weather with very little precipitation in sight for much of the region. I’m still holding with my idea of a rain-to-snow situation in much of north Illinois, southern Michigan, Missouri and Kansas. Another design idea that works is locating the deck on the side of the home that is opposite any prevailing winds. We can confirm this by viewing Figure 31 below, which shows a historical time series of zonal winds. There is a chance for development before upper level winds turn unfavorable. I did put a ‘Not Very Good’ chance for the 3-6 inch range (you may have to adjust it west a tad, or clip off the southern edge of the yellow zone). This is a short range forecast discussion for the period August 20-21. This discussion has been reviewed and approved by The Weather Centre for the potential for heavy rain and possible severe weather.

3. Important physical environmental constraints: There cannot be a common plan of action for developing the areas for renewable energy mainly because every location has its unique potential and physical viabilities. You can also use a formula I made a year or two ago for snow day potential by clicking here. We can use this rule to our advantage here. Spot-on flea control applied to your dog’s skin can harm your cat. When humidity is high (amount of water vapour is more in air), clothes dry slowly, sweat do not evaporate from skin and we feel sticky and uncomfortable. The string of below normal water temperatures is not extremely significant, and many of those little below-normal anomalies on this ‘string’ are only slightly below normal. If the body does not get the water it needs it can cause dehydration. Again, we cannot be sure if that is the cause of the rainfall. Again, such a strengthening storm and the tricky rain snow line makes forecasts difficult to confirm. Amounts will increase as you move northeast through this forecast in response to the storm strengthening. This system will continue to move eastward, eventually producing snow as it moves along.