After a Dry Weekend, Muggy Weather Returns for a WhileJune 11th, 2014 at 9:38 pm by Don Paul under 4 Warn Weather
After Saturday’s crisp and comfortable conditions, warming will resume on Sunday and continue to build for a good part of the week of the 16th. An upper level ridge will strengthen in the east until later in the week. Around the periphery of this ridge, several short waves will cross the Great Lakes and bring several rounds of Showers & Tshowers. The humidity will begin to build noticeably on Monday and hold into at least midweek. There is relatively good agreement in the ensemble means that some degree of troughing will redevelop near the Great Lakes later in the week, allowing more comfortable conditions to return. At this point, this cooling doesn’t appear to be likely to bring below average temperatures for any extended period. More seasonable temperatures will prevail in the mean. It can’t be determined if this weaker troughing might continue a parade of occasional short waves or not. After the early ridging during the week of the 16th, the rest of the means either favor a zonal flow or a slight WNW flow with the weaker troughing, with no visible rebuilding of the eastern ridge.
On the matter of El Nino, there continues to be some disagreement between the more conservative forecast offered by CPC on the amplitude of the event, compared to the NASA link we’d posted earlier, and some other projections. At the current time, the positive sea temp anomalies have some similarities to those observed in June 1997. However, there has also been Kelvin wave activity which has produced some of this warming. Owing to the ENSO ensemble members I’ve seen, there are only a couple of the many members which bring amplitude beyond 1.5 degrees positive anomaly. That is, most members project a Moderate El Nino. The correlation between a Moderate amplitude and WNY winter positive temperature anomalies is much less so than in the case of a Strong el nino. The hopelessly tired cliche “time will tell” applies here. We’ll have to continue to monitor the ENSO ensemble over the next several weeks to see if the trend changes.