FallsLake

And from RAH: .LONG TERM /SATURDAY THROUGH WEDNESDAY/... As of 430 AM Thursday... The focus of the long term again remains on Saturday night into Sunday morning. Latest suite of model guidance is indicating generally less snowfall amounts across the NW Piedmont, with slightly greater ice accretion. Any slight changes in the thermal profiles though can drastically change precipitation amounts and types. Synoptic setup: During the day Saturday an omega block will initially be setup across Idaho/ Montana with an upper level trough axis centered just east of Maine. Over Kansas and Missouri a shortwave trough will be lodged between the two. By late Saturday night into early Sunday morning some of the energy from the trough axis will head east while some energy remains over the Midwest. Another shortwave over California will then be pulled underneath the ridge transitioning the Omega block to a Rex block. At the surface polar surface high pressure will be located over Ontario. A surface low pressure will also be heading east across Mississippi/ Alabama. Late Saturday night into Sunday morning still shows the most impressive upper level support as surface low pressure will strengthen near the North Carolina/ South Carolina coast, with the RAH CWA located between the subtropical and polar jet streams. The split jet puts RAH in a LFQ (subtropical jet) and RRQ (polar jet). During the day Sunday multiple rounds of PVA will wash across the region as energy from the Midwest continues to eject east. Monday into Tuesday morning the remaining upper level energy will push east offshore as the block breaks down. Precip chances: Much of the day Saturday looks to be dry as 0.20" PWATs will take some time to modify. GFS forecast soundings show low level dry air (in the 700 mb to 975 mb layer) remaining through most of the day with widespread mid and upper level clouds. Saturday night into Sunday morning, or 03z Sunday into 18z Sunday, still appears to be the time period with the greatest chance of precipitation and QPF amounts. Strong DCVA and split jet dynamics (as mentioned above) will provide impressive upper level lift. Current FGEN fields also support the best QPF totals across central North Carolina (near U.S. 1). Sunday afternoon, mid and upper level dry air will pour into the region helping to support lessening PoPs. Low level saturation will remain though Monday and with the trough axis still west of the area have kept PoPs in. Precipitation type: Latest suite of model runs have advertised slightly warmer thermal profiles (and therefore thicknesses) which would support more freezing rain (and less snow) than previous runs. The best chance for wintry precipitation will be Saturday night into early Sunday morning. Taking a look at forecast soundings and max temperatures aloft, the chance for any pure snow precipitation appears transient for most of the CWA. The NAM would support some IP mixing in (at least) for most of the time across the entire CWA. The only exception would be across the far northern zones and the NW Piedmont. The ECMWF and GFS are very similar to one another with snow possible mainly along and north and west of Interstate 85. The transition looks to be quick though with only about a ~6 hr window between 00z Sunday and 06z Sunday with all snow supported. After 06z Sunday soundings profiles across the northwest change over to IP and eventually FZRA. South and east of Interstate 85 the chance of seeing pure snow falls off pretty quickly with the primary threat being FZRA. Temperatures for FZRA will be marginal, but with dewpoints Saturday afternoon in the 20s, wet bulbing should help bring lows down Sunday morning to below freezing (mainly north and west of U.S. 1). Sunday afternoon saturation in the DGZ will be lost helping to transition precipitation lighter with more of a drizzle and freezing drizzle supported. Amounts: Snowfall amounts have been decreased slightly with an inch or two possible in the Triad with amounts quickly falling off near the Triangle. Ice amounts have been raised slightly, with totals up to around a tenth of an inch possible (again mainly near Interstate 85). Tuesday into Wednesday the trough axis will be southeast of the region with weak high pressure overhead. High temperatures will slowly recover into the 50s by Wednesday. Both the ECMWF and GFS have come into better agreement here with shortwave energy heading east towards the Ohio Valley Wednesday. As of current the area looks dry Tuesday and Wednesday.

Well here is the 0z CMC for freezing rain. It's basically the last model showing a significant storm for areas from NW Ga to Charlotte to Raleigh. You would have to lean towards the other models but it is what it is:

Man what's up with the NAM. I don't know if you cry or laugh at this:

At least I'll sleep better tonight; not waking up to check the 0z model runs.

Lol...I'm not giving up hope but we really needed todays models to trend better. Maybe (just maybe) we get lucky with the Mondays event.

I was told this is where the party is....

So the 18z ICON is a nice hit for central VA to the MA. It looks like there would still be some big ice totals in the western foothills and NW Piedmont. Edit: It does create some backside snow (Monday) as talked about...

Yep time to head to the other room. Even the 18z ICON is coming in more north.

RAH states the possibility (Monday snow), but doesn't think it will be much. I would say overall there's nothing to be excited about right now (for us). It's definitely possible that changes, but just not probable. RAH: .LONG TERM /FRIDAY THROUGH WEDNESDAY/... As of 315 PM Wednesday... Fri/Fri night: The axis of the flat mid level ridge will shift eastward toward and over the Carolinas during this period, while at the surface, chilly high pressure extends in from the N. A stable and dry column with downslope 850 mb flow will allow for considerable sunshine Fri, but high clouds will increase from the W late Fri through Fri night with the onset of high level WAA ahead of the approaching central CONUS trough. Low level thicknesses are still projected to be around 25 m below normal, supporting highs in the 40s. Lows should be in the mid 20s to around 30 Fri night. Sat-Mon: Confidence is increasing that we`ll see some kind of wintry weather over the NW Piedmont, with a liquid-only event in our SE, but it`s the frequently problematic zone in between (including the Triangle) where greater uncertainty lies, where small forecast errors in the thermal structure (both horizontally and vertically) and precip amounts can yield large sensible weather differences. -Synoptic pattern: The mid level trough will deepen as it crosses the mid Miss Valley Sat/Sat night, before shearing and elongating WSW to ENE across the Mid Atlantic region and NC Sun/Mon as it connects with a polar stream shortwave. The trough will also receive energy ejecting from the storm system moving onshore over CA Fri night, with this vorticity sliding beneath the omega block over the Rockies. At the surface, polar high pressure centered over C Ontario will extend down through NC Sat, as a surface low deepens over AR/LA. With the high remaining anchored to our N by the aforementioned polar stream trough, the source of cold air into NC will be maintained. The primary low will move E and fill over E TN through Sun as the secondary low forms and strengthens along the common boundary just off the Carolina coast. The coastal low is expected to move quickly NE over the Atlantic Sun night/Mon, but the trailing trough extending back to the S Appalachians and passage of multiple perturbations within the sheared trough axis will keep conditions unsettled. -Precip chances: Much of the area will stay dry through Sat morning, with only light precip expected in the afternoon over far W and N sections in association with passage of an elevated warm front to our NW. Precip chances will then increase W to E, peaking very late Sat night into Sun morning as a batch of stronger DPVA and upper divergence (in the left exit region of an accelerating Deep South jet) passes through. Chances should then decrease with the departure of this stronger lift along with drying aloft (mainly over S NC) Sun afternoon, although persistent deeper moisture and a lingering mid- upper shear axis across VA and N NC will necessitate holding onto low chance pops mainly across the N late Sun through Mon. -Ptype/amounts: In this sort of Miller B pattern with a primary then secondary low and a persistent cold air source, it`s common to get broad corridors of mixed ptypes, and the low level thickness pattern for this event bears this out. Precip is expected to start out Sat as a light mix of mostly rain with a little sleet and snow as cloud bases lower and the low levels wet bulb, restricted largely to the Piedmont, with low QPF. The arrival of the stronger/deeper lift will fully saturate the profile coinciding with the heaviest precip late Sat night into Sun morning, when much of the northern Piedmont should become a wintry mix, ranging from mostly rain/freezing rain in the Triangle (where surface temps should waver either side of freezing before warming to solidly above freezing in the afternoon) to mostly snow with perhaps a little sleet/freezing rain in the Triad. Sun afternoon should see a change to much lighter precip as we dry aloft (-12C to -20C). We should then trend to more drizzle and freezing drizzle, although banding on the NW side of the coastal low could re-saturate the dendritic growth region such that a flip over to mostly snow may occur. Otherwise, with the surface low exiting and the reliance on more shallow, higher-level forcing for ascent (weaker DPVA and upper divergence), coverage and intensity of any precip Sun night/Mon should be low and mostly over the N. Amounts: The range of potential ice and/or snow accumulation is large at this range, but there is the potential for a few inches of snow with this event, with the greatest chance in the Triad over to Roxboro and lower to little accumulation in the Triangle. Storm total icing of a trace to a tenth of an inch is possible across the N/W Piedmont. Overall, though, based on the fast movement of the greatest lift and the incoming drying aloft, we are unlikely to see massive totals of either snow or ice with this event. However, everyone should check back often for the latest information as this storm draws closer. -Temps: Highs each day should be generally in the mid 30s to mid 40s, although Sun is likely to be the chilliest day, with some spots in the N and NW struggling just past the freezing mark. Lows both Sat night and Sun night will be in the upper 20s to mid 30s. Tue-Wed: With the trough axis likely having pushed to our SE by Tue morning, we should see a recovery trend, with rising heights aloft and thicknesses heading back up closer to normals. But confidence in the details at this range is low, as the models take pockets of northern stream energy with varying speeds, amplitudes, and paths southeastward through the Mid Atlantic region. And the 00z/09 ECMWF also ejects a southern stream wave from the deep low off the CA coast Mon and takes it eastward toward NC through mid week. Given the low predictability, will keep the forecast dry and tranquil, with temps inching closer to normal by Wed. -GIH &&

For NW NC up into VA this looks wintery. For others like RDU to Charlotte to the up state, there's two camps of models: Euro and GFS - We mostly rain. Euro did show some extra development on Monday but you really can't trust that. CMC, UKMET, ICON, and NAVGEM - Good chances of an ice storm Not sure about the JMA. The Ensembles look better than the operational (GFS & euro) but still not sure with them. So personally, I need to see the euro and GFS come back around. My confidence will stay low until they do.

Yeah, at hr 72 definitely more north; but conversely CAD looks a little stronger.

So the good thing is the GEFS is still south of the GFS.

A little bit closer to the coast as well. Still off the coast, but folks in central NC want this storm to stay in the Atlantic to have any hope.

Current employment at NOAA:

lol...oh come on man...you could get some really good video.

CMC is actually worse (or good if you like ice). 12z CMC freezing rain at hr 102):

Pivotal hasn't updated on freezing rain yet, but just looking at the Tropical Tidbits map it's about the same as 0z (bad ice storm for us). The 12z GFS is still mostly rain for the RDU folks but it wouldn't take much of a south shift to change that.

The 12z CMC looks very close to its last run. Specifically for RDU has about the same impacts. A little more snow for the NW NC folks.

Here's the CMC freezing rain from last night (0z, hr 120):

The 12z NAM did drop south (some) from its 6z run (which was a little better then the 0z). **we still have more model watching

Still a little time for this to trend back more favorably; and when I say that I mean getting a big sleet fest over downed power lines.

Euro was a big step back for us, but as NCSNOW just posted the eps was farther south. As always the case when we're tracking a storm, the 12z runs will be huge.

6z GEFS was better then 0z. The low is slightly weaker, slightly farther SE (at hr 108), and the high/CAD configuration is better.

Lol..I know man. But the GFS did go south at 6Z. I'll have to admit I didn't like the euro run from last night.

I'm not sure it's over. The 6z ICON and even the 0z CMC brings ice into your area.