IFR and LIFR over CLT

LIFR conditions dominated most of the Eastern U.S. this morning thanks to a strong low spinning its way northeast. The GOES-R LIFR probabilities (Figure 1) showed a fairly broad area of high probabilities extending from Mississippi northeast into Ohio. This area corresponded well to the observed flight rules for the same time period.

20140812 0945 GOES-R LIFR probabilities

However, also check out the area of very low probabilities over CLT, where flight rules were also observed at LIFR for most of the afternoon. Interestingly, the IFR product also showed much lower probabilities (Figure 2). Why? Well, note how smoothed both the IFR and LIFR probability appear. This suggests that only the model parameters were contributing to the FLS output.

20140812 0945 UTC GOES-R IFR probabilties

The GeoColor shows why this happened (Figure 3). At night this imagery highlights low stratus clouds in pink while keeping higher clouds in white. Note the area of pink associated with the western area of LIFR, while the eastern area over CLT corresponded with a layer of higher clouds. This higher layer of clouds subsequently prevented any satellite data from being assimilated into the probability products.

Figure 3. 20140812 0945 UTC GeoColor