constrain fall models to only predict into fall

[sdtaylor]

ie look at this picture. how are the high elevation places getting predictions in may?

[sdtaylor]

model used to make the above forecast. version 3 for alnus_incana_498
alnus_incana_498_fa8658c0-5b6b-11e8-9625-008cfac93c84.json

{
    "model_name": "WeightedEnsemble",
    "core_models": [
        {
            "parameters": {
                "time_length": 12.33388006466923,
                "time_start": 243.4017034176526,
                "intercept": 59.48677500911571,
                "slope": 10.698639837079934
            },
            "model_name": "Linear",
            "weight": 0.8362609638119555
        },
        {
            "parameters": {
                "t1": 236.221276770595,
                "F": 30.00025842043948,
                "T": 16.33593723678215
            },
            "model_name": "FallCooling",
            "weight": 0.1637390361880438
        }
    ]
}