The track models (including Invest) aren't put out by the NHC in the most reliable format. For instance.....the main reports that they put out are at 00Z, 06Z, 12Z, and 18Z. Four times per day, 6 hrs apart. Unfortunately, right now I only check for the latest one of those 4 reports. They also put out intermediate reports at say 01Z, 07Z, maybe 11Z, etc. . I'm not sure why they do this, other than the models for a particular storm may not be ready yet. In any case, the way I coded by client was the check for the very latest file by timestamp (the youngest file), the check to see if it one of the {00,06,12,18) set. If it isn't, then I check the next oldest file until I find one that falls into the (00,06,12,18) set so that I have the "official" report. The problem is that sometimes the official 6hr ones don't get updated with the proper information, they just put out one of those intermediate files. So to maybe make it a little more clear (I tend to ramble) here's a typical situation if say we are tracking 3 storms(2 invests, and 1 proper named):
00Z - Invest1, Invest2, Franklin 06Z - Invest2, Franklin 07Z - invest1 12Z - Invest1, Invest2, Franklin 18Z - Invest1, Invest2, Franklin 00Z - Invest1, Franklin 01Z - Invest2
So you can see that sometimes all of the storms aren't included in a single 6hr report. I will be working on this problem tomorrow. Odds are that if you're missing a storm that you think should be there, it will be there upon the next update.
On another note, I've upped the resolution of the SST overlays DRAMATICALLY and they look great now.....I'm going to try and get the Tropical Atlantic built into the feed tonight.