GoAPPS

"Winter in Waiting" On Saturday, rime ice covered the evergreens at the highest peaks of the Blue Ridge Parkway as autumn filled the valleys with golden hues.

Excessive Rainfall Discussion NWS Weather Prediction Center College Park MD 104 PM EDT Fri Oct 9 2026 Day 2 Valid 12Z Sat Oct 10 2026 - 12Z Sun Oct 11 2026 ...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE SOUTHEAST UNITED STATES... ...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR SOUTHEAST CALIFORNIA AND FAR SOUTHERN NEVADA... ...Southeast (Isaias)... ...1700Z Update... A Moderate Risk of Excessive Rainfall was introduced for portions of the western Carolinas southward into northern Georgia given latest QPF trends. Additional details will follow shortly. Bann Previous Forecast Discussion... The threat of heavy rainfall and flash flooding from Isaias will continue over a large portion of the Southeast on Saturday and Saturday Night. The latest outlook is very consistent with the previous forecast, with mostly small changes to account for the latest guidance and updated forecasts from NHC. See www.hurricanes.gov for the latest forecast information on all hazards associated with Isaias. Although the Slight Risk area is large, there are several areas of note where the threat is somewhat higher (on the high end of the 15 to 40 percent probabilistic range associated with that risk category), and could warrant an upgrade to a Moderate Risk in the future if guidance becomes more consistent and/or the potential for locally significant rainfall and flash flooding increases. 1. Convective rain band east of the center of Isaias (Florida Big Bend into much of Georgia). There is high confidence in a convective rain band setting up about 200 miles east of the track of the center of Isaias. This will ramp up Friday Night and likely be ongoing on Saturday morning. Given the access to moderate instability and precipitable water values approaching 2.5 inches, the rain rates could be intense at times (2-3 inches per hour). The key uncertainties are how far north the strongest convection will be able to reach, and how stationary the band will be overall. The 00Z HRRR suggested some northern limit to the extent of the instability due to a wedge of cooler air associated with a surface ridge and northeasterly low-level flow from the Piedmont of the Carolinas down into northern Georgia. However, other models suggest the effective warm front will lift further north and bring locations near Atlanta under risk of greater rain rates. This will be monitored for the need for a risk upgrade. 2. Southern Appalachians (far northeast Georgia, far upstate South Carolina, western North Carolina). Model QPF has been increasing in general in this region; for example, the NBM QPF in the upslope areas of western North Carolina has increased from a general 1-3 inches to 3-5 inches in the past 12 hours of updated runs. A contributing factor is the event coming into view of the hi-res model runs, of which many are showing more terrain enhancement and a wetter forecast, but there are some overall adjustments to the ensemble envelope with some trends in the overall forecast of Isaias. Not all hi-res models are suggestive of the highest rain rates reaching this region -- the 00Z HRRR kept instability suppressed further south with a wedge of cooler air in place closer to the mountains. However, other hi-res models are beginning to suggest double digit totals are not out of the question depending on the mesoscale details (particularly strength and orientation of the low-mid level flow and available instability). It is noted here that a Moderate Risk upgrade was strongly considered, but after collaboration with WFO GSP and the uncertainties described here, it was held at a high-end Slight Risk for now. Continued model trends in a wetter direction and reduction in rainfall uncertainty would likely drive an upgrade later today. ...

Isaias is now a major hurricane. 7:20 AM CDT Fri Oct 09 Location: 27.0°N 87.6°W Moving: NNE at 15 mph Min pressure: 959 mb Max sustained: 120 mph

And here's a rainbow that appeared for a few minutes after the storm passed. Both shots were from my DJI Air2S drone.

Late to the party, but here's a drone shot of the storm that hit Asheville.

Snowing in Asheville now. 34°.

As Met pointed showed above, the GFS and now several short-range models are showing a deformation zone forming as the trough goes neutral and the cyclone begins occluding, wrapping moisture back into the colder air mass on the northwest side of the system. The window is very narrow, so odds are low, but it could surprise some folks with a burst of snow.

The Costco mushroom yard lights look great in the snow!

It's only through 1 p.m. tomorrow. Here's through 1 p.m. Sunday. Also adds a good thumping of NWFS for the mountains.

Latest GSP Forecast Discussion has some interesting tidbits. By Saturday, guidance digs the potent upper low in the vicinity of the Upstate as it evolves into a negative tilt and instigates subsequent surface cyclogenesis along a coastal baroclinic zone. The upper low will be anomalously deep with H5 heights in the bottom 1st percentile to near all time record low for the southeast. This will be an unusually cold snow event for the western Carolinas and northeast Georgia with very cold temperatures in place as the snow occurs. Some members of guidance depict temperatures in the low 20s to teens during peak snowfall rates on Saturday and even the warmer solutions keep temperatures at 30 degrees or lower. Furthermore, forecast soundings indicate incredibly cold profiles with a deep dendritic growth zone and plenty of forcing in part from strong DPVA with the upper low. This will result in rare SLRs ranging from 15:1 to 20:1. Surprisingly, guidance is in very good agreement with SLRs with only small differences between the 10th and 90th percentiles. Thus, it won`t take much liquid QPF to realize several inches of snow. The very cold temperatures will also increase impacts to travel with snow sticking very efficiently to roads.

That's a good bet, but I'd wait until Friday morning before making a final decision.

Timing is everything with this weekend's system. The Euro phases the upper low later and farther east, leaving the mountains with cold air aloft but limited divergence and moisture. The GFS phases earlier, allowing stronger upper-level divergence to overlap deeper moisture and throw precip back into the Appalachians.

Up to 33 degrees in West Asheville with only a light glaze.

I’m guessing those lower totals in the southwest mountains are from the Euro amping the system so much that it changes over to just plain rain? Not complaining, if we’re not gonna get any snow, I’d rather it just be rain.

Any thoughts on an undermodeled CAD leading to the surface low tracking further south than modeled?

That wind could bump us from a 2 to a 4 or even worse.

We better pray that doesn't verify.

I really hope this is snow and not ice, not just because ice sucks, but also because Asheville and the surrounding area could really use a break from infrastructure-wreaking storms.

I'm really hoping these suppressed solutions don't pan out, though it would be hilarious if Wilmington got more snow than Asheville for the second year in a row. Last year it was 2.6" for Wilmington and 1.9" for Asheville.

Next Tuesday is looking tantalizingly close.

View of Melissa’s eye at peak intensity. Credit: European Union, Copernicus Sentinel-2 satellite.

Look at the size of the stadium effect on shortwave IR.

I hope this isn't a dumb question, but is there a website similar to Tropical Tidbits or Pivotal Weather where I can see graphical representations of Google AI model products?

Just to illustrate the difficulty of this forecast, here are the 500mb height anomalies from the 0z Euro, Euro AI, and GFS. They clearly show that 94L's eventual track is hugely dependent on the speed and placement of both 94L and Humberto when they have their Fujiwhara interaction. Three scenarios are showing up. In the GFS solution, Humberto throws 94L into the South Carolina coast, and it quickly moves inland. Scenario 2, shown by the Euro, has Humberto partially capturing 94L, causing it to stall right on the S.C. coast but eventually releasing it. Again, 94L strikes the S.C. coast, but a bit further south and weaker. The Euro AI has a weaker and faster Humberto, which interacts earlier with 94L and causes that same stalling further out to sea. When 94L eventually gets free, it heads out to sea instead of west.

Current runs of the GFS and Euro show the western tropical system hitting South Carolina.