Good day everyone!
Well, it appears yesterday’s forecast was bust. You’ve heard me mention GIGO (Garbage in, Garbage out) as far as model information goes. Evidently this is what appears to have happened, as analysis of parameters were pretty much in agreement with the models analyzed, and with information contained in the SPC outlook yesterday. Specific targeting showed a threat for strong tornadoes, isolated, for yesterday as outlined.
The SPC has indicated a SLIGHT risk of Severe Thunderstorms FROM PARTS OF THE TN VALLEY NORTHEASTWARD INTO NEW ENGLAND…
Based on analysis of the outlook, substantial destabilization is expect to occur over the area, as skies are clear at the moment, which will allow for daytime surface heating. Based on the 12Z soundings from around the area, the atmosphere is pretty stable at the moment. Analysis of F5 Data Severe Weather software, the SWEAT index indicates the severity of storms should be limited, however a tornado or two cannot be ruled out from any rotating supercell structures. Please refer to the SPC home page (linked in map) for updated information on Watches, Mesoscale Discussions, and updates to the outlook.
The only model to go on at the moment is the GFS, as the other Global models do not extend out 2 weeks. The GFS has now been more consistent in developing a weak tropical system in the SW Caribbean around the June 3-5 time period. Albeit I am going to wait until this solution begins to show up on other models around the 6-10 day time period, the GFS has appeared to have some good consistency now. Should this trend continue, this solution may not be able to be completely ruled out, as the ESRL 500 mb Mean Anomaly maps for the period, do tend to indicate a lowering of pressures in the SW Caribbean, albeit most of the falls are confined to the EPAC. The setup of ridging over the eastern U.S., and lowering pressures south, are indicative of a classic situational development setup.
ESRL 500 MB MEAN ANOMALY
Another item which may be of concern is, the current run of the GFS wind shear forecast map indicates an upper level anticyclone developing in the EPAC in approximately 144-150 hours, and progressing northward over Central America, which would tend to suggest further progression to the SW Caribbean. This will all be monitored over the next 5-7 days for consistency.
Elsewhere, the most recent Operational SST Anomaly map suggests more indications this season may very well be above normal activity. The following factors are noted in analysis of this map:
1.) SST Anomalies are running 2.0 – 2.5 C above average in the MDR.
2.) Cooler anomalies continue to maintain and spread over Nino regions 3 and 3.4
3.) The Atlantic Ocean Tripole is well established.
4.) The IOD (Indian Ocean DiPole) is negative. If this signal remains, it has the tendency to not disrupt the African Monsoonal Circulation off West Africa.
5.) The Gulf of Guinea has been cooling, and is almost at 100% cooler anomalies. This allows for the ITCZ/Monsoon trof to migrate northward, which begins to bring rainfall into the western Sahel region of Africa.
6.) The PDO (Pacific Decadal Oscillation) has continued to warm, and is currently displaying anomalies similar to June of 2004.
The majority of Dynamic Model Ensembles indicate the presence of the MJO in Octant 1 by the end of this month, through the fourth of June.
MJO INDEX FORECAST
I will continue to monitor this, and will begin issuance of the Tropical Weather synopsis June 01.
Have a blessed day!
T. F. “STORM” WALSH III
GMCS, USCG (ret)
METEOROLOGIST / HURRICANE SPECIALIST
MEMBER WEST CENTRAL FL AMS
CERTIFIED SKYWARN OFFICIAL STORM SPOTTER (advanced)