Here we go again, record highs in danger
Well above average temperatures will headline the weather story through Sunday.
Today and Tonight: Beyond morning fog, a partly sunny afternoon is ahead with high temperatures pegged for the upper 70s. Especially where there is ample sunshine, the 1989 record of 80 degrees is certainly in danger. Like Wednesday, a shower is not impossible, but any flare up would be light and short-lived. Winds will remain southerly at 5-10mph. More fog is expected overnight with a low temperature in the low 60s.
Up Next: Friday through Sunday will bring partly cloudy skies with highs in the upper 70s and lows in the low 60s. Each morning brings the possibility of patchy fog, but other than that, there are no major weather concerns. Though warm, the forecast for runners in the Louisiana Marathon, Half, Quarter and 5K is looking dry with light winds and falling humidity through the races. The next chance for organized showers and thunderstorms will hold off until Monday.
THE SCIENCE: A fast zonal flow in the upper levels will leave a stationary front in position north of the forecast area through the weekend. As moisture advection continues, a few low-topped showers could pop, but overall, the main story will remain above average temperatures. As southerly flow continues south of the aforementioned stalled boundary, highs will make a run for 80 degrees on Thursday and Friday. This seems possible as 500mb model progs the thickest atmosphere both days. Temperatures have only been scaled back a degree or two for Saturday and Sunday as mid-level riding over the Gulf of Mexico begins to flatten and move east. Low level moisture shown at 80-90 percent on 850/700mb forecast charts suggests at least partly cloudy if not mostly cloudy skies through the weekend. However, an absence of significant forcing mechanisms will mean that rain chances stay at 20 percent or less in that time. By early next week, an amplifying dip in the jet stream over the South Central United States should begin to help along the boundary to our northwest. Increased forcing due to the advancing front should result in better shower and thunderstorm chances for Monday and Tuesday. While the WECMWF is fairly wet Monday and Tuesday, the GFS is not. For now, a blend of the two models has been used to forecast rain amounts in the 1” range. Even after the front kicks through next week, a significant cool down is not expected.