Support fetching ionosonde data for FoF2 and MUF display on the Conditions page

config-example.yml

@@ -183,6 +183,10 @@ solar-condition-providers:
     class: "NOAA3dayForecast"
     name: "NOAA 3-day Forecast"
     enabled: true
+  -
+    class: "GIROIonosonde"
+    name: "GIRO Ionosonde Data"
+    enabled: true
 
 # Port to open the local web server on
 web-server-port: 8080

data/solar_conditions.py

@@ -161,6 +161,8 @@ class SolarConditions:
     blackout_forecast_r1r2: dict = None
     # NOAA Radio Blackout (R3 or greater) probability forecast, keyed by UNIX timestamp of start of day UTC
     blackout_forecast_r3_or_greater: dict = None
+    # Ionosonde measurements from LGDC, list of dicts with keys: ursi, name, fof2, muf
+    ionosonde_data: list = None
 
     # Derived values (populated by infer_descriptions())
     # HF radio blackout risk description, derived from xray

datafiles/didbase-stations.csv

@@ -0,0 +1,42 @@
+AA343,"Almaty, Kazakhstan"
+AL945,"Alpena, United States"
+AT138,"Athens, Greece"
+AU930,"Austin, United States"
+BR52P,"Brisbane, Australia"
+BVJ03,"Boa Vista, Brazil"
+CAJ2M,"Cachoeira Paulista, Brazil"
+CB53N,"Canberra, Australia"
+CGK21,"Campo Grande, Brazil"
+DB049,"Dourbes, Belgium"
+DW41K,"Darwin, Australia"
+EA036,"El Arenosillo, Spain"
+EB040,"Roquetes, Spain"
+EG931,"Eglin Air Force Base, United States"
+FF051,"Fairford, United Kingdom"
+GA762,"Gakona, United States"
+GM037,"Gibilmanna, Italy"
+GR13L,"Grahamstown, South Africa"
+HE13N,"Hermanus, South Africa"
+HO54K,"Hobart, Australia"
+IC437,"I-Cheon, South Korea"
+IF843,"Idaho National Laboratory, United States"
+JI91J,"Jicamarca, Peru"
+JR055,"Juliusruh, Germany"
+LAA38,"Lajes Terceira Island, Portugal"
+LL721,"Lualualei, United States"
+LM42B,"Learmonth, Australia"
+LV12P,"Louisvale, South Africa"
+MHJ45,"Millstone Hill, United States"
+ML10L,"Malindi, Kenya"
+NI135,"Nicosia, Cyprus"
+NI63_,"Norfolk, Australia"
+PA836,"Portt Arguello, United States"
+PE43K,"Perth, Australia"
+PF765,"Poker Flat, United States"
+PQ052,"Pruhonice, Czechia"
+RO041,"Rome, Italy"
+SAA0K,"Saoluis, Brazil"
+SO148,"Sopron, Hungary"
+TR169,"Tromso, Norway"
+TV51R,"Townsville, Australia"
+VT139,"San Vito, Italy"

server/handlers/pagetemplate.py

@@ -11,11 +11,12 @@ from core.prometheus_metrics_handler import page_requests_counter
 class PageTemplateHandler(tornado.web.RequestHandler):
     """Handler for all HTML pages generated from templates"""
 
-    def initialize(self, template_name, web_server_metrics, has_hamqsl=False, has_noaa_forecast=False):
+    def initialize(self, template_name, web_server_metrics, has_hamqsl=False, has_noaa_forecast=False, has_giro_ionosonde=False):
         self._template_name = template_name
         self._web_server_metrics = web_server_metrics
         self._has_hamqsl = has_hamqsl
         self._has_noaa_forecast = has_noaa_forecast
+        self._has_giro_ionosonde = has_giro_ionosonde
 
     def get(self):
         # Metrics
@@ -27,4 +28,5 @@ class PageTemplateHandler(tornado.web.RequestHandler):
         # Load named template, and provide variables used in templates
         self.render(self._template_name + ".html", software_version=SOFTWARE_VERSION, allow_spotting=ALLOW_SPOTTING,
                     web_ui_options=WEB_UI_OPTIONS, baseurl=BASE_URL, current_path=self.request.path,
-                    has_hamqsl=self._has_hamqsl, has_noaa_forecast=self._has_noaa_forecast)
+                    has_hamqsl=self._has_hamqsl, has_noaa_forecast=self._has_noaa_forecast,
+                    has_giro_ionosonde=self._has_giro_ionosonde)

server/webserver.py

@@ -57,8 +57,9 @@ class WebServer:
         provider_classes = [type(p).__name__ for p in self._solar_condition_providers if p.enabled]
         has_hamqsl = "HamQSL" in provider_classes
         has_noaa_forecast = "NOAA3dayForecast" in provider_classes
+        has_giro_ionosonde = "GIROIonosonde" in provider_classes
         page_opts = {"web_server_metrics": self.web_server_metrics, "has_hamqsl": has_hamqsl,
-                     "has_noaa_forecast": has_noaa_forecast}
+                     "has_noaa_forecast": has_noaa_forecast, "has_giro_ionosonde": has_giro_ionosonde}
 
         app = tornado.web.Application([
             # Routes for API calls

solarconditionsproviders/giroionosonde.py

@@ -0,0 +1,122 @@
+import csv
+import logging
+from datetime import datetime, timezone, timedelta
+from threading import Thread, Event
+
+import pytz
+import requests
+
+from core.constants import HTTP_HEADERS
+from solarconditionsproviders.solar_conditions_provider import SolarConditionsProvider
+
+POLL_INTERVAL = 3600  # 1 hour
+STATIONS_INDEX = "datafiles/didbase-stations.csv"
+LGDC_URL = "https://lgdc.uml.edu/common/DIDBGetValues"
+HISTORY_HOURS = 24
+
+
+class GIROIonosonde(SolarConditionsProvider):
+    """Solar conditions provider using ionosonde data from the GIRO Data Center.
+    Queries foF2 and MUF measurements for all stations in datafiles/didbase-stations.csv."""
+
+    def __init__(self, provider_config):
+        super().__init__(provider_config)
+        self._stations = self._load_stations()
+        self._thread = None
+        self._stop_event = Event()
+
+    def _load_stations(self):
+        """Load the CSV file containing the list of URSIs and Station Names for currently active ionosondes."""
+
+        stations = []
+        with open(STATIONS_INDEX, newline='') as f:
+            for row in csv.reader(f):
+                if len(row) >= 2:
+                    stations.append({"ursi": row[0].strip(), "name": row[1].strip()})
+        return stations
+
+    def start(self):
+        logging.info(f"Set up query of GIRO ionosonde data API every {POLL_INTERVAL} seconds.")
+        self._thread = Thread(target=self._run, daemon=True)
+        self._thread.start()
+
+    def stop(self):
+        self._stop_event.set()
+
+    def _run(self):
+        while True:
+            self._poll()
+            if self._stop_event.wait(timeout=POLL_INTERVAL):
+                break
+
+    def _poll(self):
+        try:
+            logging.debug(f"Polling {self.name} ionosonde data...")
+            now = datetime.now(timezone.utc)
+            from_time = now - timedelta(hours=HISTORY_HOURS)
+            results = []
+
+            for station in self._stations:
+                if self._stop_event.is_set():
+                    break
+                ursi = station["ursi"]
+                name = station["name"]
+                entry = {"ursi": ursi, "name": name, "fof2": None, "muf": None}
+                try:
+                    fof2, muf = self._fetch_station_data(ursi, from_time, now)
+                    entry["fof2"] = fof2
+                    entry["muf"] = muf
+                    if fof2 and muf:
+                        results.append(entry)
+                except Exception:
+                    logging.debug(f"Could not fetch ionosonde data for {ursi} ({name})")
+
+            self.update_data({"ionosonde_data": results})
+            self.status = "OK"
+            self.last_update_time = datetime.now(pytz.UTC)
+            logging.debug(f"Received ionosonde data for {len(results)} stations from {self.name}.")
+
+        except Exception:
+            self.status = "Error"
+            logging.exception(f"Exception in GIRO Ionosonde data provider ({self.name})")
+            self._stop_event.wait(timeout=1)
+
+    def _fetch_station_data(self, ursi, from_time, to_time):
+        """Fetch foF2 and MUF readings for a station. Returns (fof2_dict, muf_dict) keyed by UNIX timestamp."""
+
+        from_str = from_time.strftime("%Y.%m.%d+%H:%M:%S")
+        to_str = to_time.strftime("%Y.%m.%d+%H:%M:%S")
+        url = (
+            f"{LGDC_URL}?ursiCode={ursi}&charName=foF2,MUFD&DMUF=3000&fromDate={from_str}&toDate={to_str}"
+        )
+        response = requests.get(url, headers=HTTP_HEADERS, timeout=(5, 15))
+        if response.status_code != 200:
+            return None, None
+        return self._parse_all(response.text)
+
+    @staticmethod
+    def _parse_all(text):
+        """Parse web server response and return (fof2_dict, muf_dict) keyed by UNIX timestamp."""
+
+        fof2_data = {}
+        muf_data = {}
+        for line in text.splitlines():
+            line = line.strip()
+            if not line or line.startswith('#'):
+                continue
+            # Data rows: timestamp CS foF2 QD MUFD QD
+            parts = line.split()
+            if len(parts) >= 5:
+                try:
+                    ts = datetime.fromisoformat(parts[0].replace('Z', '+00:00')).timestamp()
+                except ValueError:
+                    continue
+                try:
+                    fof2_data[ts] = float(parts[2])
+                except ValueError:
+                    pass
+                try:
+                    muf_data[ts] = float(parts[4])
+                except ValueError:
+                    pass
+        return fof2_data, muf_data

templates/about.html

@@ -27,7 +27,7 @@
     <h4 class="mt-4">What data sources are supported?</h4>
     <p>Spothole can retrieve spots from: <a href="https://www.dxcluster.info/telnet/">Telnet-based DX clusters</a>, the <a href="https://www.reversebeacon.net/">Reverse Beacon Network (RBN)</a>, the <a href="https://www.aprs-is.net/">APRS Internet Service (APRS-IS)</a>, <a href="https://pota.app">POTA</a>, <a href="https://www.sota.org.uk/">SOTA</a>, <a href="https://wwff.co/">WWFF</a>, <a href="https://www.cqgma.org/">GMA</a>, <a href="https://wwbota.net/">WWBOTA</a>, <a href="http://www.hema.org.uk/">HEMA</a>, <a href="https://www.parksnpeaks.org/">Parks 'n' Peaks</a>, <a href="https://ontheair.nz">ZLOTA</a>, <a href="https://www.wota.org.uk/">WOTA</a>, <a href="https://llota.app">LLOTA</a>, <a href="https://wwtota.com">WWTOTA</a>, <a href="https://tilesontheair.com/">Tiles on the Air</a>, the <a href="https://ukpacketradio.network/">UK Packet Repeater Network</a>, and any site based on the <a href="https://github.com/nischu/xOTA">xOTA software by nischu</a>.</p>
     <p>Spothole can retrieve alerts from: <a href="https://www.ng3k.com/">NG3K</a>, <a href="https://pota.app">POTA</a>, <a href="https://www.sota.org.uk/">SOTA</a>, <a href="https://wwff.co/">WWFF</a>, <a href="https://www.parksnpeaks.org/">Parks 'n' Peaks</a>, <a href="https://www.wota.org.uk/">WOTA</a> and <a href="https://www.beachesontheair.com/">BOTA</a>.</p>
-    <p>Spothole can retrieve solar and propagation condition data from <a href="https://www.hamqsl.com">HamQSL</a>.</p>
+    <p>Spothole can retrieve solar and propagation condition data from <a href="https://www.hamqsl.com">HamQSL</a>, the <a href="https://www.swpc.noaa.gov/">NOAA Space Weather Prediction Center</a> and the <a href="https://giro.uml.edu/">Lowell GIRO Data Center</a>.</p>
     <p>Spothole can also perform lookups for callsign data on behalf of the user from <a href="https://qrz.com">QRZ.com</a> and <a href="https://hamqth.com">HamQTH</a>.</p>
     <p>Note that the server owner has not necessarily enabled all these data sources. In particular it is common to disable RBN, to avoid the server being swamped with FT8 traffic, and to disable APRS-IS and UK Packet Net so that the server only displays stations where there is likely to be an operator physically present for a QSO.</p>
     <p>Between the various data sources, the following Special Interest Groups (SIGs) are supported: Parks on the Air (POTA), Summits on the Air (SOTA), Worldwide Flora & Fauna (WWFF), Global Mountain Activity (GMA), Worldwide Bunkers on the Air (WWBOTA), HuMPs Excluding Marilyns Award (HEMA), Islands on the Air (IOTA), Mills on the Air (MOTA), the Amateur Radio Lighthouse Socirty (ARLHS), International Lighthouse Lightship Weekend (ILLW), Silos on the Air (SIOTA), World Castles Award (WCA), New Zealand on the Air (ZLOTA), Keith Roget Memorial National Parks Award (KRMNPA), Wainwrights on the Air (WOTA), Beaches on the Air (BOTA), Lagos y Lagunas On the Air (LLOTA), Towers on the Air (WWTOTA), Tiles on the Air, Worked All Britain (WAB), Worked All Ireland (WAI), and Toilets on the Air (TOTA).</p>
@@ -69,7 +69,7 @@
     <p>This software is dedicated to the memory of Tom G1PJB, SK, a friend and colleague who sadly passed away around the time I started writing it in Autumn 2025. I was looking forward to showing it to you when it was done.</p>
 </div>
 
-<script src="/js/common.js?v=1778853559"></script>
+<script src="/js/common.js?v=1778865954"></script>
 <script>$(document).ready(function() { $("#nav-link-about").addClass("active"); }); <!-- highlight active page in nav --></script>
 
 {% end %}

templates/add_spot.html

@@ -69,8 +69,8 @@
 
 </div>
 
-<script src="/js/common.js?v=1778853559"></script>
+<script src="/js/common.js?v=1778865954"></script>
-<script src="/js/add-spot.js?v=1778853559"></script>
+<script src="/js/add-spot.js?v=1778865954"></script>
 <script>$(document).ready(function() { $("#nav-link-add-spot").addClass("active"); }); <!-- highlight active page in nav --></script>
 
 {% end %}

templates/alerts.html

@@ -70,8 +70,8 @@
 
 </div>
 
-<script src="/js/common.js?v=1778853559"></script>
+<script src="/js/common.js?v=1778865955"></script>
-<script src="/js/alerts.js?v=1778853559"></script>
+<script src="/js/alerts.js?v=1778865955"></script>
 <script>$(document).ready(function() { $("#nav-link-alerts").addClass("active"); }); <!-- highlight active page in nav --></script>
 
 {% end %}

templates/bands.html

@@ -76,9 +76,9 @@
 <script>
     let spotProvidersEnabledByDefault = {% raw json_encode(web_ui_options["spot-providers-enabled-by-default"]) %};
 </script>
-<script src="/js/common.js?v=1778853559"></script>
+<script src="/js/common.js?v=1778865954"></script>
-<script src="/js/spotsbandsandmap.js?v=1778853559"></script>
+<script src="/js/spotsbandsandmap.js?v=1778865954"></script>
-<script src="/js/bands.js?v=1778853559"></script>
+<script src="/js/bands.js?v=1778865954"></script>
 <script>$(document).ready(function() { $("#nav-link-bands").addClass("active"); }); <!-- highlight active page in nav --></script>
 
 {% end %}

templates/base.html

@@ -24,7 +24,7 @@
 
     <title>Spothole</title>
 
-    <link rel="stylesheet" href="/css/style.css?v=1778853559" type="text/css">
+    <link rel="stylesheet" href="/css/style.css?v=1778865954" type="text/css">
     <link href="https://cdn.jsdelivr.net/npm/bootstrap@5.3.8/dist/css/bootstrap.min.css" rel="stylesheet"
           integrity="sha384-sRIl4kxILFvY47J16cr9ZwB07vP4J8+LH7qKQnuqkuIAvNWLzeN8tE5YBujZqJLB" crossorigin="anonymous">
     <link href="/fa/css/fontawesome.min.css" rel="stylesheet" />
@@ -52,9 +52,9 @@
             integrity="sha384-L1eE4eD41kpBIWe2I0eHy+GnEUC4RIpcvibVW2JCminuPlTl+2Bc528iPdVMg5Dn"
             crossorigin="anonymous"></script>
 
-    <script src="https://misc.ianrenton.com/jsutils/utils.js?v=1778853559"></script>
+    <script src="https://misc.ianrenton.com/jsutils/utils.js?v=1778865954"></script>
-    <script src="https://misc.ianrenton.com/jsutils/ui-ham.js?v=1778853559"></script>
+    <script src="https://misc.ianrenton.com/jsutils/ui-ham.js?v=1778865954"></script>
-    <script src="https://misc.ianrenton.com/jsutils/geo.js?v=1778853559"></script>
+    <script src="https://misc.ianrenton.com/jsutils/geo.js?v=1778865954"></script>
 
 </head>
 <body>

templates/conditions.html

@@ -137,7 +137,7 @@
 {% if has_noaa_forecast %}
 <div class="card mt-5">
     <div class="card-header">
-        Forecast
+        Solar Weather Forecast
     </div>
     <div class="card-body">
         <div class="row mb-4">
@@ -173,6 +173,25 @@
 </div>
 {% end %}
 
+{% if has_giro_ionosonde %}
+<div class="card mt-5">
+    <div class="card-header">
+        Critical Frequency and Maximum Usable Frequency
+    </div>
+    <div class="card-body">
+        <div class="mb-3">
+            <label for="ionosonde-station" class="form-label">Ionosonde station:</label>
+            <select id="ionosonde-station" class="form-select storeable-select d-inline-block ms-2"
+                    style="width: auto;" oninput="ionosondeStationChanged();">
+            </select>
+        </div>
+        <div id="ionosonde-latest" class="mb-3"></div>
+        <canvas id="ionosonde-chart" class="mt-3 mb-3 d-none d-md-block"></canvas>
+        <div class="form-text mt-2">Data from the <a href="https://lgdc.uml.edu/">Lowell GIRO Data Center</a>.</div>
+    </div>
+</div>
+{% end %}
+
 <div class="card mt-5">
     <div class="card-header">
         DX Opportunities
@@ -230,8 +249,8 @@
 </div>
 
 <script src="https://cdn.jsdelivr.net/npm/chart.js@4.4.9/dist/chart.umd.min.js"></script>
-<script src="/js/common.js?v=1778853559"></script>
+<script src="/js/common.js?v=1778865954"></script>
-<script src="/js/conditions.js?v=1778853559"></script>
+<script src="/js/conditions.js?v=1778865954"></script>
 <script>$(document).ready(function () {
     $("#nav-link-conditions").addClass("active");
 }); <!-- highlight active page in nav --></script>

templates/map.html

@@ -94,9 +94,9 @@
 <script>
     let spotProvidersEnabledByDefault = {% raw json_encode(web_ui_options["spot-providers-enabled-by-default"]) %};
 </script>
-<script src="/js/common.js?v=1778853559"></script>
+<script src="/js/common.js?v=1778865955"></script>
-<script src="/js/spotsbandsandmap.js?v=1778853559"></script>
+<script src="/js/spotsbandsandmap.js?v=1778865955"></script>
-<script src="/js/map.js?v=1778853559"></script>
+<script src="/js/map.js?v=1778865955"></script>
 <script>$(document).ready(function() { $("#nav-link-map").addClass("active"); }); <!-- highlight active page in nav --></script>
 
 {% end %}

templates/spots.html

@@ -104,9 +104,9 @@
 <script>
     let spotProvidersEnabledByDefault = {% raw json_encode(web_ui_options["spot-providers-enabled-by-default"]) %};
 </script>
-<script src="/js/common.js?v=1778853559"></script>
+<script src="/js/common.js?v=1778865954"></script>
-<script src="/js/spotsbandsandmap.js?v=1778853559"></script>
+<script src="/js/spotsbandsandmap.js?v=1778865954"></script>
-<script src="/js/spots.js?v=1778853559"></script>
+<script src="/js/spots.js?v=1778865954"></script>
 <script>$(document).ready(function() { $("#nav-link-spots").addClass("active"); }); <!-- highlight active page in nav --></script>
 
 {% end %}

templates/status.html

@@ -59,8 +59,8 @@
     </div>
 </div>
 
-<script src="/js/common.js?v=1778853559"></script>
+<script src="/js/common.js?v=1778865954"></script>
-<script src="/js/status.js?v=1778853559"></script>
+<script src="/js/status.js?v=1778865954"></script>
 <script>
     $(document).ready(function() { $("#nav-link-status").addClass("active"); }); <!-- highlight active page in nav -->
 </script>

webassets/apidocs/openapi.yml

@@ -13,6 +13,10 @@ info:
     
     ## Changelog
     
+    ### 1.4
+
+    * `/solar` response now includes `ionosonde_data`, a list of ionosonde station measurements (foF2 and MUF) sourced from the GIRO Data Center.
+
     ### 1.3
 
     * `/spots`, `/spots/stream`, `/alerts`, `/alerts/stream`, and `/lookup/call` now accept optional QRZ.com and HamQTH credentials as query parameters. When supplied, returned data is enriched with operator name, home location etc. from those services.
@@ -1683,6 +1687,46 @@ components:
           type: string
           description: Electron flux impact description, derived from electron flux level.
           example: "No impact"
+        ionosonde_data:
+          type: array
+          nullable: true
+          description: >
+            Ionosonde measurements from the GIRO Data Center, covering active stations listed in the
+            system. Only stations for which data was successfully retrieved are included. Null if the
+            GIROIonosonde provider has not yet completed its first poll.
+          items:
+            $ref: '#/components/schemas/IonosondeStation'
+
+    IonosondeStation:
+      type: object
+      description: Ionosonde measurement data for a single station, covering approximately the last 24 hours.
+      properties:
+        ursi:
+          type: string
+          description: URSI code identifying the ionosonde station.
+          example: DB049
+        name:
+          type: string
+          description: Human-readable name of the ionosonde station.
+          example: Dourbes
+        fof2:
+          type: object
+          nullable: true
+          description: F2 layer critical frequency (foF2) measurements in MHz, keyed by UNIX timestamp (UTC seconds since epoch) of each measurement.
+          additionalProperties:
+            type: number
+          example:
+            "1747267201.0": 7.45
+            "1747267501.0": 7.50
+        muf:
+          type: object
+          nullable: true
+          description: Maximum Usable Frequency (MUF) for a 3000 km path in MHz, keyed by UNIX timestamp (UTC seconds since epoch) of each measurement.
+          additionalProperties:
+            type: number
+          example:
+            "1747267201.0": 21.66
+            "1747267501.0": 21.80
 
     SolarConditionsProviderStatus:
       type: object

webassets/js/conditions.js

@@ -1,8 +1,12 @@
 // Cache for the full dxstats API response, so we can reload on the fly if the user changes the value of their continent
 // in the select box
 let dxStatsData = null;
-// Forecast chart
+// Kp forecast chart
 let kpChart = null;
+// Cache for ionosonde data from the API
+let ionosondeData = null;
+// Ionosonde foF2/MUF chart
+let ionosondeChart = null;
 
 // Load solar conditions
 function loadSolarConditions() {
@@ -109,6 +113,14 @@ function loadSolarConditions() {
                 electronFlux <= 100 ? 'bg-success-subtle' : electronFlux <= 1000 ? 'bg-warning-subtle' : 'bg-danger-subtle');
         }
 
+        // Ionosonde
+
+        if (jsonData.ionosonde_data && jsonData.ionosonde_data.length > 0) {
+            ionosondeData = jsonData.ionosonde_data;
+            populateIonosondeDropdown(ionosondeData);
+            renderIonosondeData();
+        }
+
         // Forecast
 
         renderKIndexForecast(jsonData.k_index_forecast);
@@ -348,6 +360,203 @@ function renderBlackoutForecast(r1r2Data, r3Data) {
         .append(makeRow('R3 or greater', e => e.r3));
 }
 
+// Populate the ionosonde station dropdown and restore any saved selection
+function populateIonosondeDropdown(data) {
+    const select = $('#ionosonde-station');
+    const savedUrsi = localStorage.getItem('#ionosonde-station:value');
+    const savedValue = savedUrsi ? JSON.parse(savedUrsi) : null;
+    select.empty();
+    data.forEach(function (station) {
+        select.append($('<option>', {value: station.ursi, text: station.name}));
+    });
+    if (savedValue && select.find('option[value="' + savedValue + '"]').length) {
+        select.val(savedValue);
+    }
+}
+
+// Render the foF2/MUF data and line chart for the currently selected station
+function renderIonosondeData() {
+    if (!ionosondeData) return;
+    const ursi = $('#ionosonde-station').val();
+    if (!ursi) return;
+    const station = ionosondeData.find(function (s) {
+        return s.ursi === ursi;
+    });
+    if (!station) return;
+
+    const style = getComputedStyle(document.documentElement);
+    const fof2Color = style.getPropertyValue('--bs-primary').trim();
+    const mufColor = style.getPropertyValue('--bs-danger').trim();
+    const textColor = style.getPropertyValue('--bs-body-color').trim() || '#666';
+    const gridColor = style.getPropertyValue('--bs-border-color').trim() || 'rgba(128,128,128,0.3)';
+
+    function toSeries(dict) {
+        if (!dict) return [];
+        return Object.entries(dict)
+            .map(([tsStr, val]) => ({ts: parseFloat(tsStr), val}))
+            .sort((a, b) => a.ts - b.ts);
+    }
+
+    const fof2Entries = toSeries(station.fof2);
+    const mufEntries = toSeries(station.muf);
+    const allTs = [...fof2Entries, ...mufEntries].map(e => e.ts);
+    if (allTs.length === 0) return;
+
+    // Populate latest values summary (visible on all screen sizes)
+    const latestFof2 = fof2Entries.length ? fof2Entries[fof2Entries.length - 1].val : null;
+    const latestMuf = mufEntries.length ? mufEntries[mufEntries.length - 1].val : null;
+    const latestTs = allTs.length ? Math.max(...allTs) : null;
+    var latestTimeStr = '';
+    if (latestTs != null) {
+        const latestDate = moment.utc(latestTs * 1000);
+        latestTimeStr = latestDate.format('DD MMM YYYY HH:mm [UTC]') + ' (' + latestDate.fromNow() + ')';
+    }
+    $('#ionosonde-latest').html(
+        '<div class="row border-bottom align-items-center me-0">' +
+        '<div class="col-12 col-md-6 py-2 text-muted">Latest values as of ' + latestTimeStr + '</div>' +
+        '<div class="col-12 col-md-6 py-2">' +
+        '<span class="me-5">foF2: <strong>' + (latestFof2 !== null ? latestFof2.toFixed(2) + ' MHz' : 'N/A') + '</strong></span>' +
+        '<span>MUF (3000 km): <strong>' + (latestMuf !== null ? latestMuf.toFixed(2) + ' MHz' : 'N/A') + '</strong></span>' +
+        '</div>' +
+        '</div>'
+    );
+
+    if (ionosondeChart) {
+        ionosondeChart.destroy();
+    }
+
+    const minTs = Math.min(...allTs);
+    const maxTs = Math.max(...allTs);
+
+    // Compute tick positions at 3-hour UTC boundaries so midnight always lands on a tick, which triggers the date being
+    // printed, and in general looks nicer than arbitrary ticks based on min & max timestamp
+    const tickStep = 3 * 3600;
+    const tickValues = [];
+    for (let t = Math.ceil(minTs / tickStep) * tickStep; t <= maxTs; t += tickStep) {
+        tickValues.push(t);
+    }
+    tickValues.push(maxTs);
+
+    const timeAxis = {
+        type: 'linear',
+        min: minTs,
+        max: maxTs,
+        title: {display: true, text: 'Time (UTC)', color: textColor},
+        afterBuildTicks(axis) {
+            axis.ticks = tickValues.map(v => ({value: v}));
+        },
+        ticks: {
+            color: textColor,
+            maxRotation: 45,
+            minRotation: 0,
+            callback(value) {
+                const dt = new Date(value * 1000);
+                const h = dt.getUTCHours();
+                const m = dt.getUTCMinutes();
+                const timeStr = String(h).padStart(2, '0') + ':' + String(m).padStart(2, '0');
+                if (h === 0 && m === 0) {
+                    return [timeStr, dt.toLocaleDateString('en-GB', {day: '2-digit', month: 'short', timeZone: 'UTC'})];
+                }
+                return timeStr;
+            },
+        },
+        grid: {color: gridColor},
+    };
+
+    const freqAxis = {
+        min: 0,
+        title: {display: true, text: 'Frequency (MHz)', color: textColor},
+        ticks: {color: textColor},
+        grid: {display: false},
+    };
+
+    const AMATEUR_BANDS = [
+        {label: '160m', freq: 1.8},
+        {label: '80m', freq: 3.5},
+        {label: '60m', freq: 5.3515},
+        {label: '40m', freq: 7.0},
+        {label: '30m', freq: 10.1},
+        {label: '20m', freq: 14.0},
+        {label: '17m', freq: 18.068},
+        {label: '15m', freq: 21.0},
+        {label: '12m', freq: 24.89},
+        {label: '10m', freq: 28.0},
+    ];
+
+    const bandLinesPlugin = {
+        id: 'bandLines',
+        beforeDatasetsDraw(chart) {
+            const {ctx, chartArea, scales} = chart;
+            if (!scales.y) return;
+            ctx.save();
+            ctx.strokeStyle = gridColor;
+            ctx.lineWidth = 1;
+            ctx.setLineDash([]);
+            const y30 = scales.y.getPixelForValue(30);
+            if (y30 >= chartArea.top && y30 <= chartArea.bottom) {
+                ctx.beginPath();
+                ctx.moveTo(chartArea.left, y30);
+                ctx.lineTo(chartArea.right, y30);
+                ctx.stroke();
+            }
+            ctx.font = '10px sans-serif';
+            ctx.fillStyle = textColor;
+            AMATEUR_BANDS.forEach(({label, freq}) => {
+                const y = scales.y.getPixelForValue(freq);
+                if (y < chartArea.top || y > chartArea.bottom) return;
+                ctx.beginPath();
+                ctx.moveTo(chartArea.left, y);
+                ctx.lineTo(chartArea.right, y);
+                ctx.stroke();
+                ctx.textAlign = 'right';
+                ctx.textBaseline = 'bottom';
+                ctx.fillText(label, chartArea.right - 4, y - 2);
+            });
+            ctx.restore();
+        }
+    };
+
+    ionosondeChart = new Chart(document.getElementById('ionosonde-chart'), {
+        type: 'line',
+        data: {
+            datasets: [
+                {
+                    label: 'foF2',
+                    data: fof2Entries.map(e => ({x: e.ts, y: e.val})),
+                    borderColor: fof2Color,
+                    backgroundColor: 'transparent',
+                    pointRadius: 0,
+                    tension: 0.2,
+                },
+                {
+                    label: 'MUF (3000 km)',
+                    data: mufEntries.map(e => ({x: e.ts, y: e.val})),
+                    borderColor: mufColor,
+                    backgroundColor: 'transparent',
+                    pointRadius: 0,
+                    tension: 0.2,
+                }
+            ]
+        },
+        options: {
+            responsive: true,
+            aspectRatio: 3,
+            plugins: {
+                legend: {display: true, labels: {color: textColor, usePointStyle: true, pointStyle: 'line'}},
+                tooltip: {enabled: false}
+            },
+            scales: {x: timeAxis, y: freqAxis},
+        },
+        plugins: [bandLinesPlugin],
+    });
+}
+
+// Called when the ionosonde station select changes
+function ionosondeStationChanged() {
+    saveSettings();
+    renderIonosondeData();
+}
+
 // Render the DX stats table for the currently selected DE continent
 function renderDxStats() {
     if (!dxStatsData) {