Unseasonably mild conditions will return to dominate the next 1-2 weeks, with another trend toward above average precipitation developing as well during this extended 5-10+ day range ( remember that October is climatologically the driest month of the year ).
The anomalous warmth of September is exemplified by a 68.5 degree average daily maximum on Eagle Knob of the High Knob Massif, which just beat the 68.4 degree average daily max observed during August!
How often are average September high temperatures warmer than August? A question to be researched, but a quick look through the Wise database from 1955 to 2012 reveals NONE. NADA. No year had a September with warmer mean highs than August!
Signs of a major pattern change are beginning to show up in the far extended range, by mid-late October into November as a late developing, central-Pacific based El Nino ( +ENSO ) continues to form and exerts more influence upon the synoptic-scale flow fields across the Northern Hemispere ( along with other factors ).
Overnight Into Monday Morning
Partly cloudy then increasing clouds toward morning. Areas of dense valley fog. Winds S-SW at 5-10 mph with higher gusts on mid-upper elevation mountain ridges. Temps varying from lower 50s to the low 60s ( coolest in mountain valleys at upper elevations ).
Monday Afternoon
Partly-mostly cloudy. Chance of hit-miss showers and thunderstorms. Light SSW to SW winds generally less than 10 mph. Temperatures varying from mid-upper 60s to the mid-upper 70s ( coolest in upper elevations ).
Monday Night Into Tuesday Morning
Mostly cloudy. Chance of a shower. SW-W winds 5-10 mph with some higher gusts on mid-upper elevation mountain ridges. Temperatures in the upper 50s to middle 60s. Areas of valley fog.
Tuesday Morning Through The Afternoon
Chance of showers & thunderstorms. SW-W winds 5-15 mph, with some higher gusts on mountain ridges. Temps varying from the 60s to the middle 70s ( coolest in upper elevations ).
Tuesday Night Into Wednesday Morning
Partly-mostly cloudy. Chance of a shower. Areas of dense fog. Winds WSW-WNW at 5-10 mph on mid-upper elevation mountain ridges. Temperatures varying from the middle 50s to the middle 60s.
Reference the High Knob Hellbender 10K section for a forecast specifically designed for this race in coming days ( my Cloudspitter 100 forecast will be featured during coming weeks in advance of this race ).
Weather Discussion ( More Of Same )
A brief cooling trend which came just in time for the 12th Annual High Knob Naturalist Rally will become a memory through coming days.
High Knob Lake Recreation Area – High Knob Naturalist Rally 2018
A buoy line can be seen across the lake in the far distance to keep kayaks and canoes safely away from the overflowing High Knob Lake Dam. Up to 3.50″ of rain were reported in the area immediately prior to the Naturalist Rally.
Temperatures in the 50s to lower 60s were observed during the time of this year’s High Knob Naturalist Rally ( 7:00 AM to 5:30 PM below ), with morning low clouds and fog slowly giving way to some welcomed afternoon sunshine.
Eagle Knob of High Knob Massif ( Time UTC )
Temperatures in the 50s during much of the rally were in rather dramatic contrast to 70s-lower 80s in the Tri-Cities, with some visitors seen shivering ( and talking about the chill ).
Beautiful Water Flowing Into High Knob Lake – 2018 Naturalist Rally
Mean averages during the next week to 10 days will be lower given decreasing sun angles, but nothing close to reality for this point in the year ( see graphics below ).
Approaching Sunset – Upper Norton Reservoir – September 29, 2018
While trees are changing again in spurts, the combination of atypical mildness + a lack of frost + anthracnose fungi impacts are making it slower and duller so far. The final result yet to be determined; however, clearly these ingredients are far from ideal and have already caused some significant leaf drop ( especially at the higher elevations above 3500 feet ).
European 51-Member Ensemble Mean 500 MB Height Anomalies: Days 1-5
A deepening western USA upper trough will turn flow more S-SW across the eastern USA over time, renewing the above average precipitation pattern.
European 51-Member Ensemble Mean 500 MB Height Anomalies: Days 6-10
While some signs of a major change are beginning to show up in the far extended range, the next 1-2 weeks are looking anomalously mild at this present time.
European 51-Member Ensemble Mean 850 MB Temp Anomalies: Days 1-5
Warm anomalies in the 6-10 day range ( below ) increase due to both a combination of deeper southerly flow from the tropics and to climatology, given temperatures should be declining ( in the mean ) moving through October.
European 51-Member Ensemble Mean 850 MB Temp Anomalies: Days 6-10
This could be setting the region up for a HUGE temperature crash once a change finally occurs, and this pattern flips from current upper air ridging into upper troughing.
