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Forecast Discussion:
With a big ridge over the middle nation, we have bone dry weather with near record to record high temperatures expected much of the rest of this week. Figure 1 shows that big ridge axis to our east with southwest flow locally. That flow is bringing in clearer air (with some smoke and haze stuck in the downwind side of the Rockies - Figure 2). That's all I've got to say about our home town.
Let's look out into the future for the next cool down and off to the East Coast and Florence...
The longer range forecast:
The 500mb map for Saturday afternoon is shown in Figure 3. The ridge axis shifts east to possibly trap Florence in North Carolina and Virginia (more on this below) but the ridge is still holding strong in the western U.S. as well. A narrow trough is hanging out on the West coast with short waves breaking off and traveling up into Canada over the ridge. That is quite a blob of high pressure!
The next trough that will push in appears to approach Monday/Tuesday next week (Figure 4). We have a while to wait for that possible taste of Fall. Note that moisture from Florence is still hanging out around North Carolina and Virginia into the middle of next week.
The current National Hurricane Center (NOAA) forecast for Hurricane Florence (Figure 5) shows that southern and central parts of North Carolina are under the gun for the storm's damage. The landfall spot is looking like it will be located along the northern South Carolina coast or southern North Carolina coast (at category 4 strength). With the storm coming in as the big U.S. ridge rocks east, it might lose its steering winds abruptly, sit, spin, die, and dump rain over SC, NC, and western VA. Figure 6 (if it verifies) shows a wide area of 20-48 inches of rainfall. Some forecasters are rightfully describing that outcome as the greatest potential disaster for the region in recorded history. Please keep an eye on it if you know of anyone living in those states.
That is not the only hit the U.S. is expecting either... Hurricane Olivia is expected to hit the Hawaiian Islands (as it weakens) Tuesday night/Wednesday morning with torrential rainfall on the mountain slopes. According to WeatherBell forecaster Joe Bastardi, though, after the next week or two, he expects the tropics to calm down a lot with El Niño effects showing up. That is a ray of hope!
